diff --git a/core/src/avm2.rs b/core/src/avm2.rs
index 415d06f16..7c171b3ed 100644
--- a/core/src/avm2.rs
+++ b/core/src/avm2.rs
@@ -144,8 +144,20 @@ impl<'gc> Avm2<'gc> {
         target: Object<'gc>,
     ) -> Result<bool, Error> {
         use crate::avm2::events::dispatch_event;
-        let event_proto = context.avm2.system_prototypes.as_ref().unwrap().event;
-        let event_object = EventObject::from_event(context.gc_context, Some(event_proto), event);
+
+        let mut activation = Activation::from_nothing(context.reborrow());
+        let mut event_proto = activation.avm2().prototypes().event;
+        let event_constr = event_proto
+            .get_property(
+                event_proto,
+                &QName::new(Namespace::public(), "constructor"),
+                &mut activation,
+            )?
+            .coerce_to_object(&mut activation)?;
+        drop(activation);
+
+        let event_object =
+            EventObject::from_event(context.gc_context, event_constr, Some(event_proto), event);
         let mut activation = Activation::from_nothing(context.reborrow());
 
         dispatch_event(&mut activation, target, event_object)
@@ -255,7 +267,7 @@ impl<'gc> Avm2<'gc> {
         let tunit = TranslationUnit::from_abc(abc_file.clone(), domain, context.gc_context);
 
         for i in (0..abc_file.scripts.len()).rev() {
-            let mut script = tunit.load_script(i as u32, context.avm2, context.gc_context)?;
+            let mut script = tunit.load_script(i as u32, context)?;
 
             if !lazy_init {
                 script.globals(context)?;
diff --git a/core/src/avm2/activation.rs b/core/src/avm2/activation.rs
index e07a9277a..bea835983 100644
--- a/core/src/avm2/activation.rs
+++ b/core/src/avm2/activation.rs
@@ -105,20 +105,20 @@ pub struct Activation<'a, 'gc: 'a, 'gc_context: 'a> {
     /// A `scope` of `None` indicates that the scope stack is empty.
     scope: Option<GcCell<'gc, Scope<'gc>>>,
 
-    /// The base prototype of `this`.
+    /// The base class constructor that yielded the currently executing method.
     ///
     /// This will not be available if this is not a method call.
-    base_proto: Option<Object<'gc>>,
+    base_constr: Option<Object<'gc>>,
 
-    /// The proto of all objects returned from `newactivation`.
+    /// The constructor of all objects returned from `newactivation`.
     ///
     /// In method calls that call for an activation object, this will be
     /// configured as the anonymous class whose traits match the method's
     /// declared traits.
     ///
     /// If this is `None`, then the method did not ask for an activation object
-    /// and we will not construct a prototype for one.
-    activation_proto: Option<Object<'gc>>,
+    /// and we will not allocate a constructor for one.
+    activation_constr: Option<Object<'gc>>,
 
     pub context: UpdateContext<'a, 'gc, 'gc_context>,
 }
@@ -144,8 +144,8 @@ impl<'a, 'gc, 'gc_context> Activation<'a, 'gc, 'gc_context> {
             return_value: None,
             local_scope: ScriptObject::bare_object(context.gc_context),
             scope: None,
-            base_proto: None,
-            activation_proto: None,
+            base_constr: None,
+            activation_constr: None,
             context,
         }
     }
@@ -185,8 +185,8 @@ impl<'a, 'gc, 'gc_context> Activation<'a, 'gc, 'gc_context> {
             return_value: None,
             local_scope: ScriptObject::bare_object(context.gc_context),
             scope,
-            base_proto: None,
-            activation_proto: None,
+            base_constr: None,
+            activation_constr: None,
             context,
         })
     }
@@ -194,12 +194,12 @@ impl<'a, 'gc, 'gc_context> Activation<'a, 'gc, 'gc_context> {
     /// Construct an activation for the execution of a particular bytecode
     /// method.
     pub fn from_method(
-        context: UpdateContext<'a, 'gc, 'gc_context>,
+        mut context: UpdateContext<'a, 'gc, 'gc_context>,
         method: Gc<'gc, BytecodeMethod<'gc>>,
         scope: Option<GcCell<'gc, Scope<'gc>>>,
         this: Option<Object<'gc>>,
         arguments: &[Value<'gc>],
-        base_proto: Option<Object<'gc>>,
+        base_constr: Option<Object<'gc>>,
         callee: Object<'gc>,
     ) -> Result<Self, Error> {
         let body: Result<_, Error> = method
@@ -227,22 +227,18 @@ impl<'a, 'gc, 'gc_context> Activation<'a, 'gc, 'gc_context> {
             }
         }
 
-        let activation_proto = if method.method().needs_activation {
+        let activation_constr = if method.method().needs_activation {
             let translation_unit = method.translation_unit();
             let abc_method = method.method();
-            let activation_class = Class::from_method_body(
-                context.avm2,
-                context.gc_context,
-                translation_unit,
-                abc_method,
-                body,
-            )?;
+            let activation_class =
+                Class::from_method_body(&mut context, translation_unit, abc_method, body)?;
+            let mut dummy_activation = Activation::from_nothing(context.reborrow());
+            let (constr, _cinit) =
+                ClassObject::from_class(&mut dummy_activation, activation_class, None, scope)?;
 
-            Some(ScriptObject::bare_prototype(
-                context.gc_context,
-                activation_class,
-                scope,
-            ))
+            drop(dummy_activation);
+
+            Some(constr)
         } else {
             None
         };
@@ -256,8 +252,8 @@ impl<'a, 'gc, 'gc_context> Activation<'a, 'gc, 'gc_context> {
             return_value: None,
             local_scope: ScriptObject::bare_object(context.gc_context),
             scope,
-            base_proto,
-            activation_proto,
+            base_constr,
+            activation_constr,
             context,
         };
 
@@ -274,15 +270,18 @@ impl<'a, 'gc, 'gc_context> Activation<'a, 'gc, 'gc_context> {
                 unreachable!();
             };
 
+            let mut array_proto = activation.avm2().prototypes().array;
+            let array_constr = array_proto
+                .get_property(
+                    array_proto,
+                    &QName::new(Namespace::public(), "constructor"),
+                    &mut activation,
+                )?
+                .coerce_to_object(&mut activation)?;
             let mut args_object = ArrayObject::from_array(
                 args_array,
-                activation
-                    .context
-                    .avm2
-                    .system_prototypes
-                    .as_ref()
-                    .unwrap()
-                    .array,
+                array_constr,
+                array_proto,
                 activation.context.gc_context,
             );
 
@@ -318,7 +317,7 @@ impl<'a, 'gc, 'gc_context> Activation<'a, 'gc, 'gc_context> {
         context: UpdateContext<'a, 'gc, 'gc_context>,
         scope: Option<GcCell<'gc, Scope<'gc>>>,
         this: Option<Object<'gc>>,
-        base_proto: Option<Object<'gc>>,
+        base_constr: Option<Object<'gc>>,
     ) -> Result<Self, Error> {
         let local_registers = GcCell::allocate(context.gc_context, RegisterSet::new(0));
 
@@ -331,8 +330,8 @@ impl<'a, 'gc, 'gc_context> Activation<'a, 'gc, 'gc_context> {
             return_value: None,
             local_scope: ScriptObject::bare_object(context.gc_context),
             scope,
-            base_proto,
-            activation_proto: None,
+            base_constr,
+            activation_constr: None,
             context,
         })
     }
@@ -369,20 +368,17 @@ impl<'a, 'gc, 'gc_context> Activation<'a, 'gc, 'gc_context> {
         receiver: Object<'gc>,
         args: &[Value<'gc>],
     ) -> Result<Value<'gc>, Error> {
-        let name = QName::new(Namespace::public(), "constructor");
-        let base_proto: Result<Object<'gc>, Error> =
-            self.base_proto().and_then(|p| p.proto()).ok_or_else(|| {
+        let base_constr: Result<Object<'gc>, Error> = self
+            .base_constr()
+            .and_then(|c| c.base_class_constr())
+            .ok_or_else(|| {
                 "Attempted to call super constructor without a superclass."
                     .to_string()
                     .into()
             });
-        let mut base_proto = base_proto?;
+        let base_constr = base_constr?;
 
-        let function = base_proto
-            .get_property(receiver, &name, self)?
-            .coerce_to_object(self)?;
-
-        function.call(Some(receiver), args, self, Some(base_proto))
+        base_constr.call(Some(receiver), args, self, Some(base_constr))
     }
 
     /// Attempts to lock the activation frame for execution.
@@ -452,8 +448,8 @@ impl<'a, 'gc, 'gc_context> Activation<'a, 'gc, 'gc_context> {
 
     /// Get the base prototype of the object that the currently executing
     /// method was retrieved from, if one exists.
-    pub fn base_proto(&self) -> Option<Object<'gc>> {
-        self.base_proto
+    pub fn base_constr(&self) -> Option<Object<'gc>> {
+        self.base_constr
     }
 
     /// Retrieve a int from the current constant pool.
@@ -542,7 +538,7 @@ impl<'a, 'gc, 'gc_context> Activation<'a, 'gc, 'gc_context> {
     ) -> Result<GcCell<'gc, Class<'gc>>, Error> {
         method
             .translation_unit()
-            .load_class(index.0, self.context.avm2, self.context.gc_context)
+            .load_class(index.0, &mut self.context)
     }
 
     pub fn run_actions(
@@ -817,10 +813,19 @@ impl<'a, 'gc, 'gc_context> Activation<'a, 'gc, 'gc_context> {
         value: Index<AbcNamespace>,
     ) -> Result<FrameControl<'gc>, Error> {
         let ns = self.pool_namespace(method, value, self.context.gc_context)?;
+        let mut ns_proto = self.context.avm2.prototypes().namespace;
+        let ns_constr = ns_proto
+            .get_property(
+                ns_proto,
+                &QName::new(Namespace::public(), "constructor"),
+                self,
+            )?
+            .coerce_to_object(self)?;
 
         self.context.avm2.push(NamespaceObject::from_namespace(
             ns,
-            self.context.avm2.prototypes().namespace,
+            ns_constr,
+            ns_proto,
             self.context.gc_context,
         )?);
         Ok(FrameControl::Continue)
@@ -952,11 +957,15 @@ impl<'a, 'gc, 'gc_context> Activation<'a, 'gc, 'gc_context> {
             .resolve_multiname(&multiname)?
             .ok_or_else(|| format!("Could not find method {:?}", multiname.local_name()).into());
         let name = name?;
-        let base_proto = receiver.get_base_proto(&name)?;
+        let base_constr = if let Some(c) = receiver.as_constr() {
+            c.find_base_constr_for_trait(&name)?
+        } else {
+            None
+        };
         let function = receiver
             .get_property(receiver, &name, self)?
             .coerce_to_object(self)?;
-        let value = function.call(Some(receiver), &args, self, base_proto)?;
+        let value = function.call(Some(receiver), &args, self, base_constr)?;
 
         self.context.avm2.push(value);
 
@@ -998,12 +1007,16 @@ impl<'a, 'gc, 'gc_context> Activation<'a, 'gc, 'gc_context> {
             .resolve_multiname(&multiname)?
             .ok_or_else(|| format!("Could not find method {:?}", multiname.local_name()).into());
         let name = name?;
-        let base_proto = receiver.get_base_proto(&name)?;
+        let base_constr = if let Some(c) = receiver.as_constr() {
+            c.find_base_constr_for_trait(&name)?
+        } else {
+            None
+        };
         let function = receiver
             .get_property(receiver, &name, self)?
             .coerce_to_object(self)?;
 
-        function.call(Some(receiver), &args, self, base_proto)?;
+        function.call(Some(receiver), &args, self, base_constr)?;
 
         Ok(FrameControl::Continue)
     }
@@ -1025,7 +1038,7 @@ impl<'a, 'gc, 'gc_context> Activation<'a, 'gc, 'gc_context> {
             self.context.avm2.prototypes().function,
             None,
         );
-        let value = function.call(Some(receiver), &args, self, receiver.proto())?;
+        let value = function.call(Some(receiver), &args, self, receiver.as_constr())?;
 
         self.context.avm2.push(value);
 
@@ -1041,23 +1054,23 @@ impl<'a, 'gc, 'gc_context> Activation<'a, 'gc, 'gc_context> {
         let args = self.context.avm2.pop_args(arg_count);
         let multiname = self.pool_multiname(method, index)?;
         let receiver = self.context.avm2.pop().coerce_to_object(self)?;
+
         let name: Result<QName, Error> = receiver
             .resolve_multiname(&multiname)?
             .ok_or_else(|| format!("Could not find method {:?}", multiname.local_name()).into());
-        let base_proto: Result<Object<'gc>, Error> =
-            self.base_proto().and_then(|bp| bp.proto()).ok_or_else(|| {
+        let name = name?;
+
+        let base_constr: Result<Object<'gc>, Error> = self
+            .base_constr()
+            .and_then(|bc| bc.base_class_constr())
+            .ok_or_else(|| {
                 "Attempted to call super method without a superclass."
                     .to_string()
                     .into()
             });
-        let base_proto = base_proto?;
-        let mut base = base_proto.construct(self, &[])?; //TODO: very hacky workaround
+        let base_constr = base_constr?;
 
-        let function = base
-            .get_property(receiver, &name?, self)?
-            .coerce_to_object(self)?;
-
-        let value = function.call(Some(receiver), &args, self, Some(base_proto))?;
+        let value = base_constr.call_instance_method(&name, Some(receiver), &args, self)?;
 
         self.context.avm2.push(value);
 
@@ -1073,23 +1086,23 @@ impl<'a, 'gc, 'gc_context> Activation<'a, 'gc, 'gc_context> {
         let args = self.context.avm2.pop_args(arg_count);
         let multiname = self.pool_multiname(method, index)?;
         let receiver = self.context.avm2.pop().coerce_to_object(self)?;
+
         let name: Result<QName, Error> = receiver
             .resolve_multiname(&multiname)?
             .ok_or_else(|| format!("Could not find method {:?}", multiname.local_name()).into());
-        let base_proto: Result<Object<'gc>, Error> =
-            self.base_proto().and_then(|bp| bp.proto()).ok_or_else(|| {
+        let name = name?;
+
+        let base_constr: Result<Object<'gc>, Error> = self
+            .base_constr()
+            .and_then(|bc| bc.base_class_constr())
+            .ok_or_else(|| {
                 "Attempted to call super method without a superclass."
                     .to_string()
                     .into()
             });
-        let base_proto = base_proto?;
-        let mut base = base_proto.construct(self, &[])?; //TODO: very hacky workaround
+        let base_constr = base_constr?;
 
-        let function = base
-            .get_property(receiver, &name?, self)?
-            .coerce_to_object(self)?;
-
-        function.call(Some(receiver), &args, self, Some(base_proto))?;
+        base_constr.call_instance_method(&name, Some(receiver), &args, self)?;
 
         Ok(FrameControl::Continue)
     }
@@ -1120,7 +1133,7 @@ impl<'a, 'gc, 'gc_context> Activation<'a, 'gc, 'gc_context> {
         // dynamic properties not yet set
         if name.is_err()
             && !object
-                .as_proto_class()
+                .as_class()
                 .map(|c| c.read().is_sealed())
                 .unwrap_or(false)
         {
@@ -1198,7 +1211,7 @@ impl<'a, 'gc, 'gc_context> Activation<'a, 'gc, 'gc_context> {
             // Unknown properties on a dynamic class delete successfully.
             self.context.avm2.push(
                 !object
-                    .as_proto_class()
+                    .as_class()
                     .map(|c| c.read().is_sealed())
                     .unwrap_or(false),
             )
@@ -1214,22 +1227,23 @@ impl<'a, 'gc, 'gc_context> Activation<'a, 'gc, 'gc_context> {
     ) -> Result<FrameControl<'gc>, Error> {
         let multiname = self.pool_multiname(method, index)?;
         let object = self.context.avm2.pop().coerce_to_object(self)?;
-        let base_proto: Result<Object<'gc>, Error> = self
-            .base_proto()
-            .and_then(|p| p.proto())
-            .ok_or_else(|| "Attempted to get property on non-existent super object".into());
-        let base_proto = base_proto?;
-        let mut base = base_proto.construct(self, &[])?; //TODO: very hacky workaround
 
-        let name: Result<QName, Error> = base.resolve_multiname(&multiname)?.ok_or_else(|| {
-            format!(
-                "Could not resolve {:?} as super property",
-                multiname.local_name()
-            )
-            .into()
-        });
+        let name: Result<QName, Error> = object
+            .resolve_multiname(&multiname)?
+            .ok_or_else(|| format!("Could not find method {:?}", multiname.local_name()).into());
+        let name = name?;
 
-        let value = base.get_property(object, &name?, self)?;
+        let base_constr: Result<Object<'gc>, Error> = self
+            .base_constr()
+            .and_then(|bc| bc.base_class_constr())
+            .ok_or_else(|| {
+                "Attempted to call super method without a superclass."
+                    .to_string()
+                    .into()
+            });
+        let base_constr = base_constr?;
+
+        let value = base_constr.call_instance_getter(&name, Some(object), self)?;
 
         self.context.avm2.push(value);
 
@@ -1244,22 +1258,23 @@ impl<'a, 'gc, 'gc_context> Activation<'a, 'gc, 'gc_context> {
         let value = self.context.avm2.pop();
         let multiname = self.pool_multiname(method, index)?;
         let object = self.context.avm2.pop().coerce_to_object(self)?;
-        let base_proto: Result<Object<'gc>, Error> = self
-            .base_proto()
-            .and_then(|p| p.proto())
-            .ok_or_else(|| "Attempted to get property on non-existent super object".into());
-        let base_proto = base_proto?;
-        let mut base = base_proto.construct(self, &[])?; //TODO: very hacky workaround
 
-        let name: Result<QName, Error> = base.resolve_multiname(&multiname)?.ok_or_else(|| {
-            format!(
-                "Could not resolve {:?} as super property",
-                multiname.local_name()
-            )
-            .into()
-        });
+        let name: Result<QName, Error> = object
+            .resolve_multiname(&multiname)?
+            .ok_or_else(|| format!("Could not find method {:?}", multiname.local_name()).into());
+        let name = name?;
 
-        base.set_property(object, &name?, value, self)?;
+        let base_constr: Result<Object<'gc>, Error> = self
+            .base_constr()
+            .and_then(|bc| bc.base_class_constr())
+            .ok_or_else(|| {
+                "Attempted to call super method without a superclass."
+                    .to_string()
+                    .into()
+            });
+        let base_constr = base_constr?;
+
+        base_constr.call_instance_setter(&name, value, Some(object), self)?;
 
         Ok(FrameControl::Continue)
     }
@@ -1433,14 +1448,9 @@ impl<'a, 'gc, 'gc_context> Activation<'a, 'gc, 'gc_context> {
 
     fn op_construct(&mut self, arg_count: u32) -> Result<FrameControl<'gc>, Error> {
         let args = self.context.avm2.pop_args(arg_count);
-        let mut ctor = self.context.avm2.pop().coerce_to_object(self)?;
+        let ctor = self.context.avm2.pop().coerce_to_object(self)?;
 
-        let proto = ctor
-            .get_property(ctor, &QName::new(Namespace::public(), "prototype"), self)?
-            .coerce_to_object(self)?;
-
-        let object = proto.construct(self, &args)?;
-        ctor.call(Some(object), &args, self, object.proto())?;
+        let object = ctor.construct(self, &args)?;
 
         self.context.avm2.push(object);
 
@@ -1461,15 +1471,12 @@ impl<'a, 'gc, 'gc_context> Activation<'a, 'gc, 'gc_context> {
             source.resolve_multiname(&multiname)?.ok_or_else(|| {
                 format!("Could not resolve property {:?}", multiname.local_name()).into()
             });
-        let mut ctor = source
-            .get_property(source, &ctor_name?, self)?
-            .coerce_to_object(self)?;
-        let proto = ctor
-            .get_property(ctor, &QName::new(Namespace::public(), "prototype"), self)?
+        let ctor_name = ctor_name?;
+        let ctor = source
+            .get_property(source, &ctor_name, self)?
             .coerce_to_object(self)?;
 
-        let object = proto.construct(self, &args)?;
-        ctor.call(Some(object), &args, self, Some(proto))?;
+        let object = ctor.construct(self, &args)?;
 
         self.context.avm2.push(object);
 
@@ -1486,16 +1493,13 @@ impl<'a, 'gc, 'gc_context> Activation<'a, 'gc, 'gc_context> {
     }
 
     fn op_new_activation(&mut self) -> Result<FrameControl<'gc>, Error> {
-        if let Some(activation_proto) = self.activation_proto {
-            self.context.avm2.push(ScriptObject::object(
-                self.context.gc_context,
-                activation_proto,
-            ));
+        let instance = if let Some(activation_constr) = self.activation_constr {
+            activation_constr.construct(self, &[])?
         } else {
-            self.context
-                .avm2
-                .push(ScriptObject::bare_object(self.context.gc_context));
-        }
+            ScriptObject::bare_object(self.context.gc_context)
+        };
+
+        self.context.avm2.push(instance);
 
         Ok(FrameControl::Continue)
     }
@@ -1583,11 +1587,17 @@ impl<'a, 'gc, 'gc_context> Activation<'a, 'gc, 'gc_context> {
     fn op_new_array(&mut self, num_args: u32) -> Result<FrameControl<'gc>, Error> {
         let args = self.context.avm2.pop_args(num_args);
         let array = ArrayStorage::from_args(&args[..]);
-        let array_obj = ArrayObject::from_array(
-            array,
-            self.context.avm2.system_prototypes.clone().unwrap().array,
-            self.context.gc_context,
-        );
+        let mut array_proto = self.context.avm2.prototypes().array;
+        let array_constr = array_proto
+            .get_property(
+                array_proto,
+                &QName::new(Namespace::public(), "constructor"),
+                self,
+            )?
+            .coerce_to_object(self)?;
+
+        let array_obj =
+            ArrayObject::from_array(array, array_constr, array_proto, self.context.gc_context);
 
         self.context.avm2.push(array_obj);
 
diff --git a/core/src/avm2/class.rs b/core/src/avm2/class.rs
index 697bab503..dd5108c88 100644
--- a/core/src/avm2/class.rs
+++ b/core/src/avm2/class.rs
@@ -4,11 +4,11 @@ use crate::avm2::activation::Activation;
 use crate::avm2::method::{Method, NativeMethod};
 use crate::avm2::names::{Multiname, Namespace, QName};
 use crate::avm2::object::{Object, ScriptObject, TObject};
-use crate::avm2::scope::Scope;
 use crate::avm2::script::TranslationUnit;
 use crate::avm2::string::AvmString;
 use crate::avm2::traits::{Trait, TraitKind};
-use crate::avm2::{Avm2, Error};
+use crate::avm2::Error;
+use crate::context::UpdateContext;
 use bitflags::bitflags;
 use gc_arena::{Collect, GcCell, MutationContext};
 use std::fmt;
@@ -42,17 +42,14 @@ bitflags! {
 /// Parameters for the deriver are:
 ///
 ///  * `constr` - The class constructor that was called (or will be called) to
-///  construct this object. This may either be a base class (if we're creating
-///  a derived class prototype object) or the current class (if we're creating
-///  an instance of the new class)
+///  construct this object. This must be the current class (using a base class
+///  will cause the wrong class to be read for traits).
+///  * `proto` - The prototype attached to the class constructor.
 ///  * `activation` - This is the current AVM2 activation.
-///  * `class` - The class we are attempting to derive.
-///  * `scope` - The scope the class was declared in.
 pub type DeriverFn = for<'gc> fn(
+    Object<'gc>,
     Object<'gc>,
     &mut Activation<'_, 'gc, '_>,
-    GcCell<'gc, Class<'gc>>,
-    Option<GcCell<'gc, Scope<'gc>>>,
 ) -> Result<Object<'gc>, Error>;
 
 #[derive(Clone, Collect)]
@@ -73,9 +70,8 @@ impl fmt::Debug for Deriver {
 /// not exist, we default to `ScriptObject`.
 pub fn implicit_deriver<'gc>(
     mut constr: Object<'gc>,
+    proto: Object<'gc>,
     activation: &mut Activation<'_, 'gc, '_>,
-    class: GcCell<'gc, Class<'gc>>,
-    scope: Option<GcCell<'gc, Scope<'gc>>>,
 ) -> Result<Object<'gc>, Error> {
     let mut base_constr = Some(constr);
     let mut base_class = constr.as_class();
@@ -94,7 +90,7 @@ pub fn implicit_deriver<'gc>(
     }
 
     if let Some(base_deriver) = instance_deriver {
-        base_deriver(constr, activation, class, scope)
+        base_deriver(constr, proto, activation)
     } else {
         let base_proto = constr
             .get_property(
@@ -104,11 +100,10 @@ pub fn implicit_deriver<'gc>(
             )?
             .coerce_to_object(activation)?;
 
-        Ok(ScriptObject::prototype(
+        Ok(ScriptObject::instance(
             activation.context.gc_context,
+            constr,
             base_proto,
-            class,
-            scope,
         ))
     }
 }
@@ -349,8 +344,7 @@ impl<'gc> Class<'gc> {
         &mut self,
         unit: TranslationUnit<'gc>,
         class_index: u32,
-        avm2: &mut Avm2<'gc>,
-        mc: MutationContext<'gc, '_>,
+        uc: &mut UpdateContext<'_, 'gc, '_>,
     ) -> Result<(), Error> {
         if self.traits_loaded {
             return Ok(());
@@ -373,38 +367,32 @@ impl<'gc> Class<'gc> {
 
         for abc_trait in abc_instance.traits.iter() {
             self.instance_traits
-                .push(Trait::from_abc_trait(unit, abc_trait, avm2, mc)?);
+                .push(Trait::from_abc_trait(unit, abc_trait, uc)?);
         }
 
         for abc_trait in abc_class.traits.iter() {
             self.class_traits
-                .push(Trait::from_abc_trait(unit, abc_trait, avm2, mc)?);
+                .push(Trait::from_abc_trait(unit, abc_trait, uc)?);
         }
 
         Ok(())
     }
 
     pub fn from_method_body(
-        avm2: &mut Avm2<'gc>,
-        mc: MutationContext<'gc, '_>,
+        uc: &mut UpdateContext<'_, 'gc, '_>,
         translation_unit: TranslationUnit<'gc>,
         method: &AbcMethod,
         body: &AbcMethodBody,
     ) -> Result<GcCell<'gc, Self>, Error> {
-        let name = translation_unit.pool_string(method.name.as_u30(), mc)?;
-
+        let name = translation_unit.pool_string(method.name.as_u30(), uc.gc_context)?;
         let mut traits = Vec::with_capacity(body.traits.len());
-        for trait_entry in &body.traits {
-            traits.push(Trait::from_abc_trait(
-                translation_unit,
-                trait_entry,
-                avm2,
-                mc,
-            )?);
+
+        for trait_entry in body.traits.iter() {
+            traits.push(Trait::from_abc_trait(translation_unit, trait_entry, uc)?);
         }
 
         Ok(GcCell::allocate(
-            mc,
+            uc.gc_context,
             Self {
                 name: QName::dynamic_name(name),
                 super_class: None,
diff --git a/core/src/avm2/domain.rs b/core/src/avm2/domain.rs
index 7015cde55..142141a32 100644
--- a/core/src/avm2/domain.rs
+++ b/core/src/avm2/domain.rs
@@ -1,7 +1,7 @@
 //! Application Domains
 
 use crate::avm2::activation::Activation;
-use crate::avm2::names::{Multiname, QName};
+use crate::avm2::names::{Multiname, Namespace, QName};
 use crate::avm2::object::{ByteArrayObject, TObject};
 use crate::avm2::script::Script;
 use crate::avm2::value::Value;
@@ -25,7 +25,12 @@ struct DomainData<'gc> {
     parent: Option<Domain<'gc>>,
 
     /// The bytearray used for storing domain memory
-    pub domain_memory: ByteArrayObject<'gc>,
+    ///
+    /// Note: While this property is optional, it is not recommended to set it
+    /// to `None`. It is only optional to avoid an order-of-events problem in
+    /// player globals setup (we need a global domain to put globals into, but
+    /// that domain needs the bytearray global)
+    pub domain_memory: Option<ByteArrayObject<'gc>>,
 }
 
 impl<'gc> Domain<'gc> {
@@ -33,33 +38,41 @@ impl<'gc> Domain<'gc> {
     ///
     /// This is intended exclusively for creating the player globals domain,
     /// hence the name.
+    ///
+    /// Note: the global domain will be created without valid domain memory.
+    /// You must initialize domain memory later on after the ByteArray class is
+    /// instantiated but before user code runs.
     pub fn global_domain(mc: MutationContext<'gc, '_>) -> Domain<'gc> {
-        let domain_memory = ByteArrayObject::new(mc, None);
-        domain_memory.as_bytearray_mut(mc).unwrap().set_length(1024);
-
         Self(GcCell::allocate(
             mc,
             DomainData {
                 defs: HashMap::new(),
                 parent: None,
-                domain_memory,
+                domain_memory: None,
             },
         ))
     }
 
     /// Create a new domain with a given parent.
-    pub fn movie_domain(mc: MutationContext<'gc, '_>, parent: Domain<'gc>) -> Domain<'gc> {
-        let domain_memory = ByteArrayObject::new(mc, None);
-        domain_memory.as_bytearray_mut(mc).unwrap().set_length(1024);
-
-        Self(GcCell::allocate(
-            mc,
+    ///
+    /// This function must not be called before the player globals have been
+    /// fully allocated.
+    pub fn movie_domain(
+        activation: &mut Activation<'_, 'gc, '_>,
+        parent: Domain<'gc>,
+    ) -> Domain<'gc> {
+        let this = Self(GcCell::allocate(
+            activation.context.gc_context,
             DomainData {
                 defs: HashMap::new(),
                 parent: Some(parent),
-                domain_memory,
+                domain_memory: None,
             },
-        ))
+        ));
+
+        this.init_default_domain_memory(activation).unwrap();
+
+        this
     }
 
     /// Get the parent of this domain
@@ -159,7 +172,10 @@ impl<'gc> Domain<'gc> {
     }
 
     pub fn domain_memory(&self) -> ByteArrayObject<'gc> {
-        self.0.read().domain_memory
+        self.0
+            .read()
+            .domain_memory
+            .expect("Domain must have valid memory at all times")
     }
 
     pub fn set_domain_memory(
@@ -167,6 +183,41 @@ impl<'gc> Domain<'gc> {
         mc: MutationContext<'gc, '_>,
         domain_memory: ByteArrayObject<'gc>,
     ) {
-        self.0.write(mc).domain_memory = domain_memory
+        self.0.write(mc).domain_memory = Some(domain_memory)
+    }
+
+    /// Allocate the default domain memory for this domain, if it does not
+    /// already exist.
+    ///
+    /// This function is only necessary to be called for domains created via
+    /// `global_domain`. It will do nothing on already fully-initialized
+    /// domains.
+    pub fn init_default_domain_memory(
+        self,
+        activation: &mut Activation<'_, 'gc, '_>,
+    ) -> Result<(), Error> {
+        let mut bytearray_proto = activation.avm2().prototypes().bytearray;
+        let bytearray_constr = bytearray_proto
+            .get_property(
+                bytearray_proto,
+                &QName::new(Namespace::public(), "constructor"),
+                activation,
+            )?
+            .coerce_to_object(activation)?;
+
+        let domain_memory = ByteArrayObject::new(
+            activation.context.gc_context,
+            bytearray_constr,
+            Some(bytearray_proto),
+        );
+        domain_memory
+            .as_bytearray_mut(activation.context.gc_context)
+            .unwrap()
+            .set_length(1024);
+
+        let mut write = self.0.write(activation.context.gc_context);
+        write.domain_memory.get_or_insert(domain_memory);
+
+        Ok(())
     }
 }
diff --git a/core/src/avm2/function.rs b/core/src/avm2/function.rs
index aeae1758a..8205b8f2d 100644
--- a/core/src/avm2/function.rs
+++ b/core/src/avm2/function.rs
@@ -82,7 +82,7 @@ impl<'gc> Executable<'gc> {
         unbound_reciever: Option<Object<'gc>>,
         arguments: &[Value<'gc>],
         activation: &mut Activation<'_, 'gc, '_>,
-        base_proto: Option<Object<'gc>>,
+        base_constr: Option<Object<'gc>>,
         callee: Object<'gc>,
     ) -> Result<Value<'gc>, Error> {
         match self {
@@ -93,7 +93,7 @@ impl<'gc> Executable<'gc> {
                     activation.context.reborrow(),
                     scope,
                     receiver,
-                    base_proto,
+                    base_constr,
                 )?;
 
                 nf(&mut activation, receiver, arguments)
@@ -106,7 +106,7 @@ impl<'gc> Executable<'gc> {
                     bm.scope,
                     receiver,
                     arguments,
-                    base_proto,
+                    base_constr,
                     callee,
                 )?;
 
diff --git a/core/src/avm2/globals.rs b/core/src/avm2/globals.rs
index 9623c664f..0179c9ce5 100644
--- a/core/src/avm2/globals.rs
+++ b/core/src/avm2/globals.rs
@@ -192,10 +192,12 @@ fn function<'gc>(
 fn dynamic_class<'gc>(
     mc: MutationContext<'gc, '_>,
     constr: Object<'gc>,
-    class: GcCell<'gc, Class<'gc>>,
     mut domain: Domain<'gc>,
     script: Script<'gc>,
 ) -> Result<(), Error> {
+    let class = constr
+        .as_class()
+        .ok_or("Attempted to create builtin dynamic class without class on it's constructor!")?;
     let name = class.read().name().clone();
 
     script
@@ -288,7 +290,7 @@ pub fn load_player_globals<'gc>(
     domain: Domain<'gc>,
 ) -> Result<(), Error> {
     let mc = activation.context.gc_context;
-    let gs = DomainObject::from_domain(mc, None, domain);
+    let gs = DomainObject::from_early_domain(mc, domain);
     let script = Script::empty_script(mc, gs);
 
     // public / root package
@@ -296,18 +298,18 @@ pub fn load_player_globals<'gc>(
     // We have to do this particular dance so that we have Object methods whose
     // functions have call/apply in their prototypes, and that Function is also
     // a subclass of Object.
-    let (object_proto, object_class) = object::create_proto(activation, gs);
-    let (fn_proto, fn_class) = function::create_proto(activation, gs, object_proto);
+    let object_proto = object::create_proto(activation);
+    let fn_proto = function::create_proto(activation, object_proto);
 
-    let object_constr = object::fill_proto(activation, object_proto, fn_proto)?;
-    let function_constr = function::fill_proto(activation, fn_proto, object_constr);
+    let object_constr = object::fill_proto(activation, gs, object_proto, fn_proto)?;
+    let function_constr = function::fill_proto(activation, gs, fn_proto, object_constr);
 
-    let (class_constr, class_proto, class_class) =
+    let (class_constr, class_proto) =
         class::create_class(activation, gs, object_constr, object_proto, fn_proto);
 
-    dynamic_class(mc, object_constr, object_class, domain, script)?;
-    dynamic_class(mc, function_constr, fn_class, domain, script)?;
-    dynamic_class(mc, class_constr, class_class, domain, script)?;
+    dynamic_class(mc, object_constr, domain, script)?;
+    dynamic_class(mc, function_constr, domain, script)?;
+    dynamic_class(mc, class_constr, domain, script)?;
 
     // At this point, we need at least a partial set of system prototypes in
     // order to continue initializing the player. The rest of the prototypes
@@ -425,6 +427,9 @@ pub fn load_player_globals<'gc>(
         domain,
         script,
     )?;
+    gs.as_application_domain()
+        .unwrap()
+        .init_default_domain_memory(activation)?;
 
     class(
         activation,
@@ -436,7 +441,6 @@ pub fn load_player_globals<'gc>(
     class(
         activation,
         flash::utils::compression_algorithm::create_class(mc),
-        implicit_deriver,
         domain,
         script,
     )?;
diff --git a/core/src/avm2/globals/array.rs b/core/src/avm2/globals/array.rs
index dbb4f0026..6b2697cfa 100644
--- a/core/src/avm2/globals/array.rs
+++ b/core/src/avm2/globals/array.rs
@@ -96,15 +96,19 @@ pub fn build_array<'gc>(
     activation: &mut Activation<'_, 'gc, '_>,
     array: ArrayStorage<'gc>,
 ) -> Result<Value<'gc>, Error> {
+    let mut array_proto = activation.avm2().prototypes().array;
+    let array_constr = array_proto
+        .get_property(
+            array_proto,
+            &QName::new(Namespace::public(), "constructor"),
+            activation,
+        )?
+        .coerce_to_object(activation)?;
+
     Ok(ArrayObject::from_array(
         array,
-        activation
-            .context
-            .avm2
-            .system_prototypes
-            .as_ref()
-            .map(|sp| sp.array)
-            .unwrap(),
+        array_constr,
+        array_proto,
         activation.context.gc_context,
     )
     .into())
diff --git a/core/src/avm2/globals/class.rs b/core/src/avm2/globals/class.rs
index 6f874b882..c882ef69d 100644
--- a/core/src/avm2/globals/class.rs
+++ b/core/src/avm2/globals/class.rs
@@ -8,7 +8,6 @@ use crate::avm2::object::{ClassObject, Object, ScriptObject, TObject};
 use crate::avm2::scope::Scope;
 use crate::avm2::value::Value;
 use crate::avm2::Error;
-use gc_arena::GcCell;
 
 /// Implements `Class`'s instance initializer.
 ///
@@ -38,7 +37,7 @@ pub fn create_class<'gc>(
     super_constr: Object<'gc>,
     super_proto: Object<'gc>,
     fn_proto: Object<'gc>,
-) -> (Object<'gc>, Object<'gc>, GcCell<'gc, Class<'gc>>) {
+) -> (Object<'gc>, Object<'gc>) {
     let class_class = Class::new(
         QName::new(Namespace::public(), "Class"),
         Some(QName::new(Namespace::public(), "Object").into()),
@@ -48,20 +47,17 @@ pub fn create_class<'gc>(
     );
 
     let scope = Scope::push_scope(globals.get_scope(), globals, activation.context.gc_context);
-    let proto = ScriptObject::prototype(
-        activation.context.gc_context,
-        super_proto,
-        class_class,
-        Some(scope),
-    );
+    let proto = ScriptObject::object(activation.context.gc_context, super_proto);
 
     let constr = ClassObject::from_builtin_constr(
         activation.context.gc_context,
         Some(super_constr),
+        class_class,
+        Some(scope),
         proto,
         fn_proto,
     )
     .unwrap();
 
-    (constr, proto, class_class)
+    (constr, proto)
 }
diff --git a/core/src/avm2/globals/flash/display/displayobject.rs b/core/src/avm2/globals/flash/display/displayobject.rs
index 64a64d10d..5ce0a9490 100644
--- a/core/src/avm2/globals/flash/display/displayobject.rs
+++ b/core/src/avm2/globals/flash/display/displayobject.rs
@@ -560,6 +560,15 @@ pub fn loader_info<'gc>(
     _args: &[Value<'gc>],
 ) -> Result<Value<'gc>, Error> {
     if let Some(dobj) = this.and_then(|this| this.as_display_object()) {
+        let mut loaderinfo_proto = activation.avm2().prototypes().loaderinfo;
+        let loaderinfo_constr = loaderinfo_proto
+            .get_property(
+                loaderinfo_proto,
+                &QName::new(Namespace::public(), "constructor"),
+                activation,
+            )?
+            .coerce_to_object(activation)?;
+
         if let Some(root) = dobj.avm2_root(&mut activation.context) {
             if DisplayObject::ptr_eq(root, dobj) {
                 let movie = dobj.movie();
@@ -568,7 +577,8 @@ pub fn loader_info<'gc>(
                     let obj = LoaderInfoObject::from_movie(
                         movie,
                         root,
-                        activation.context.avm2.prototypes().loaderinfo,
+                        loaderinfo_constr,
+                        loaderinfo_proto,
                         activation.context.gc_context,
                     )?;
 
@@ -581,7 +591,8 @@ pub fn loader_info<'gc>(
 
         if DisplayObject::ptr_eq(dobj, activation.context.stage.into()) {
             return Ok(LoaderInfoObject::from_stage(
-                activation.context.avm2.prototypes().loaderinfo,
+                loaderinfo_constr,
+                loaderinfo_proto,
                 activation.context.gc_context,
             )
             .into());
diff --git a/core/src/avm2/globals/flash/display/loaderinfo.rs b/core/src/avm2/globals/flash/display/loaderinfo.rs
index a6be3d327..0ae1e11a8 100644
--- a/core/src/avm2/globals/flash/display/loaderinfo.rs
+++ b/core/src/avm2/globals/flash/display/loaderinfo.rs
@@ -66,11 +66,21 @@ pub fn application_domain<'gc>(
 ) -> Result<Value<'gc>, Error> {
     if let Some(this) = this {
         if let Some(loader_stream) = this.as_loader_stream() {
+            let mut appdomain_proto = activation.avm2().prototypes().application_domain;
+            let appdomain_constr = appdomain_proto
+                .get_property(
+                    appdomain_proto,
+                    &QName::new(Namespace::public(), "constructor"),
+                    activation,
+                )?
+                .coerce_to_object(activation)?;
+
             match &*loader_stream {
                 LoaderStream::Stage => {
                     return Ok(DomainObject::from_domain(
                         activation.context.gc_context,
-                        Some(activation.context.avm2.prototypes().application_domain),
+                        appdomain_constr,
+                        Some(appdomain_proto),
                         activation.context.avm2.global_domain(),
                     )
                     .into());
@@ -82,7 +92,8 @@ pub fn application_domain<'gc>(
                         .library_for_movie_mut(movie.clone());
                     return Ok(DomainObject::from_domain(
                         activation.context.gc_context,
-                        Some(activation.context.avm2.prototypes().application_domain),
+                        appdomain_constr,
+                        Some(appdomain_proto),
                         library.avm2_domain(),
                     )
                     .into());
@@ -290,9 +301,20 @@ pub fn bytes<'gc>(
                     return Err("Error: The stage's loader info does not have a bytestream".into())
                 }
                 LoaderStream::Swf(root, _) => {
-                    let ba_proto = activation.context.avm2.prototypes().bytearray;
-                    let ba =
-                        ByteArrayObject::construct(activation.context.gc_context, Some(ba_proto));
+                    let mut ba_proto = activation.context.avm2.prototypes().bytearray;
+                    let ba_constr = ba_proto
+                        .get_property(
+                            ba_proto,
+                            &QName::new(Namespace::public(), "constructor"),
+                            activation,
+                        )?
+                        .coerce_to_object(activation)?;
+
+                    let ba = ByteArrayObject::construct(
+                        activation.context.gc_context,
+                        ba_constr,
+                        Some(ba_proto),
+                    );
                     let mut ba_write = ba.as_bytearray_mut(activation.context.gc_context).unwrap();
 
                     // First, write a fake header corresponding to an
diff --git a/core/src/avm2/globals/flash/display/movieclip.rs b/core/src/avm2/globals/flash/display/movieclip.rs
index 635952227..c054f1386 100644
--- a/core/src/avm2/globals/flash/display/movieclip.rs
+++ b/core/src/avm2/globals/flash/display/movieclip.rs
@@ -3,7 +3,6 @@
 use crate::avm2::activation::Activation;
 use crate::avm2::array::ArrayStorage;
 use crate::avm2::class::Class;
-use crate::avm2::globals::flash::display::{framelabel, scene};
 use crate::avm2::method::{Method, NativeMethod};
 use crate::avm2::names::{Namespace, QName};
 use crate::avm2::object::{ArrayObject, Object, TObject};
@@ -163,26 +162,42 @@ fn labels_for_scene<'gc>(
         start: scene_start,
         length: scene_length,
     } = scene;
-    let frame_label_proto = activation.context.avm2.prototypes().framelabel;
+    let mut frame_label_proto = activation.context.avm2.prototypes().framelabel;
     let labels = mc.labels_in_range(*scene_start, scene_start + scene_length);
     let mut frame_labels = Vec::with_capacity(labels.len());
+    let frame_label_constr = frame_label_proto
+        .get_property(
+            frame_label_proto,
+            &QName::new(Namespace::public(), "constructor"),
+            activation,
+        )?
+        .coerce_to_object(activation)?;
+
     for (name, frame) in labels {
         let name: Value<'gc> = AvmString::new(activation.context.gc_context, name).into();
         let local_frame = frame - scene_start + 1;
         let args = [name, local_frame.into()];
-        let frame_label = frame_label_proto.construct(activation, &args)?;
-
-        framelabel::instance_init(activation, Some(frame_label), &args)?;
+        let frame_label = frame_label_constr.construct(activation, &args)?;
 
         frame_labels.push(Some(frame_label.into()));
     }
 
+    let mut array_proto = activation.avm2().prototypes().array;
+    let array_constr = array_proto
+        .get_property(
+            array_proto,
+            &QName::new(Namespace::public(), "constructor"),
+            activation,
+        )?
+        .coerce_to_object(activation)?;
+
     Ok((
         scene_name.to_string(),
         *scene_length,
         ArrayObject::from_array(
             ArrayStorage::from_storage(frame_labels),
-            activation.context.avm2.prototypes().array,
+            array_constr,
+            array_proto,
             activation.context.gc_context,
         ),
     ))
@@ -225,16 +240,21 @@ pub fn current_scene<'gc>(
             length: mc.total_frames(),
         });
         let (scene_name, scene_length, scene_labels) = labels_for_scene(activation, mc, &scene)?;
-        let scene_proto = activation.context.avm2.prototypes().scene;
+        let mut scene_proto = activation.context.avm2.prototypes().scene;
+        let scene_constr = scene_proto
+            .get_property(
+                scene_proto,
+                &QName::new(Namespace::public(), "constructor"),
+                activation,
+            )?
+            .coerce_to_object(activation)?;
         let args = [
             AvmString::new(activation.context.gc_context, scene_name).into(),
             scene_labels.into(),
             scene_length.into(),
         ];
 
-        let scene = scene_proto.construct(activation, &args)?;
-
-        scene::instance_init(activation, Some(scene), &args)?;
+        let scene = scene_constr.construct(activation, &args)?;
 
         return Ok(scene.into());
     }
@@ -265,23 +285,38 @@ pub fn scenes<'gc>(
         for scene in mc_scenes {
             let (scene_name, scene_length, scene_labels) =
                 labels_for_scene(activation, mc, &scene)?;
-            let scene_proto = activation.context.avm2.prototypes().scene;
+            let mut scene_proto = activation.context.avm2.prototypes().scene;
+            let scene_constr = scene_proto
+                .get_property(
+                    scene_proto,
+                    &QName::new(Namespace::public(), "constructor"),
+                    activation,
+                )?
+                .coerce_to_object(activation)?;
             let args = [
                 AvmString::new(activation.context.gc_context, scene_name).into(),
                 scene_labels.into(),
                 scene_length.into(),
             ];
 
-            let scene = scene_proto.construct(activation, &args)?;
-
-            scene::instance_init(activation, Some(scene), &args)?;
+            let scene = scene_constr.construct(activation, &args)?;
 
             scene_objects.push(Some(scene.into()));
         }
 
+        let mut array_proto = activation.avm2().prototypes().array;
+        let array_constr = array_proto
+            .get_property(
+                array_proto,
+                &QName::new(Namespace::public(), "constructor"),
+                activation,
+            )?
+            .coerce_to_object(activation)?;
+
         return Ok(ArrayObject::from_array(
             ArrayStorage::from_storage(scene_objects),
-            activation.context.avm2.prototypes().array,
+            array_constr,
+            array_proto,
             activation.context.gc_context,
         )
         .into());
diff --git a/core/src/avm2/globals/flash/display/shape.rs b/core/src/avm2/globals/flash/display/shape.rs
index 380b3f149..2169eecdf 100644
--- a/core/src/avm2/globals/flash/display/shape.rs
+++ b/core/src/avm2/globals/flash/display/shape.rs
@@ -62,10 +62,20 @@ pub fn graphics<'gc>(
                 activation,
             )? {
                 Value::Undefined | Value::Null => {
-                    let graphics_proto = activation.context.avm2.prototypes().graphics;
+                    let mut graphics_proto = activation.context.avm2.prototypes().graphics;
+                    let graphics_constr = graphics_proto
+                        .get_property(
+                            graphics_proto,
+                            &QName::new(Namespace::public(), "constructor"),
+                            activation,
+                        )
+                        .and_then(|v| v.coerce_to_object(activation))
+                        .expect("Video proto needs constr");
+
                     let graphics = Value::from(StageObject::for_display_object(
                         activation.context.gc_context,
                         dobj,
+                        graphics_constr,
                         graphics_proto,
                     ));
                     this.set_property(
diff --git a/core/src/avm2/globals/flash/display/sprite.rs b/core/src/avm2/globals/flash/display/sprite.rs
index e93981d65..e4b06dc36 100644
--- a/core/src/avm2/globals/flash/display/sprite.rs
+++ b/core/src/avm2/globals/flash/display/sprite.rs
@@ -48,10 +48,20 @@ pub fn graphics<'gc>(
                 activation,
             )? {
                 Value::Undefined | Value::Null => {
-                    let graphics_proto = activation.context.avm2.prototypes().graphics;
+                    let mut graphics_proto = activation.context.avm2.prototypes().graphics;
+                    let graphics_constr = graphics_proto
+                        .get_property(
+                            graphics_proto,
+                            &QName::new(Namespace::public(), "constructor"),
+                            activation,
+                        )
+                        .and_then(|v| v.coerce_to_object(activation))
+                        .expect("Video proto needs constr");
+
                     let graphics = Value::from(StageObject::for_display_object(
                         activation.context.gc_context,
                         dobj,
+                        graphics_constr,
                         graphics_proto,
                     ));
                     this.set_property(
diff --git a/core/src/avm2/globals/flash/events/event.rs b/core/src/avm2/globals/flash/events/event.rs
index 46d4f0603..ed81f49bf 100644
--- a/core/src/avm2/globals/flash/events/event.rs
+++ b/core/src/avm2/globals/flash/events/event.rs
@@ -142,10 +142,18 @@ pub fn clone<'gc>(
     _args: &[Value<'gc>],
 ) -> Result<Value<'gc>, Error> {
     if let Some(evt) = this.unwrap().as_event() {
-        let evt_proto = activation.avm2().system_prototypes.as_ref().unwrap().event;
+        let mut evt_proto = activation.avm2().prototypes().event;
+        let evt_constr = evt_proto
+            .get_property(
+                evt_proto,
+                &QName::new(Namespace::public(), "constructor"),
+                activation,
+            )?
+            .coerce_to_object(activation)?;
 
         return Ok(EventObject::from_event(
             activation.context.gc_context,
+            evt_constr,
             Some(evt_proto),
             evt.clone(),
         )
diff --git a/core/src/avm2/globals/flash/geom/point.rs b/core/src/avm2/globals/flash/geom/point.rs
index 73d0f5c56..8dd3d58d7 100644
--- a/core/src/avm2/globals/flash/geom/point.rs
+++ b/core/src/avm2/globals/flash/geom/point.rs
@@ -10,9 +10,17 @@ fn create_point<'gc>(
     activation: &mut Activation<'_, 'gc, '_>,
     coords: (f64, f64),
 ) -> Result<Value<'gc>, Error> {
-    let proto = activation.context.avm2.prototypes().point;
+    let mut point_proto = activation.context.avm2.prototypes().point;
+    let point_constr = point_proto
+        .get_property(
+            point_proto,
+            &QName::new(Namespace::public(), "constructor"),
+            activation,
+        )?
+        .coerce_to_object(activation)?;
+
     let args = [Value::Number(coords.0), Value::Number(coords.1)];
-    let new_point = proto.construct(activation, &args)?;
+    let new_point = point_constr.construct(activation, &args)?;
     instance_init(activation, Some(new_point), &args)?;
 
     Ok(new_point.into())
diff --git a/core/src/avm2/globals/flash/system/application_domain.rs b/core/src/avm2/globals/flash/system/application_domain.rs
index 2bc9e93ad..479efe7fd 100644
--- a/core/src/avm2/globals/flash/system/application_domain.rs
+++ b/core/src/avm2/globals/flash/system/application_domain.rs
@@ -39,10 +39,20 @@ pub fn current_domain<'gc>(
 ) -> Result<Value<'gc>, Error> {
     let globals = activation.scope().map(|s| s.read().globals());
     let appdomain = globals.and_then(|g| g.as_application_domain());
+    let mut appdomain_proto = activation.avm2().prototypes().application_domain;
+    let appdomain_constr = appdomain_proto
+        .get_property(
+            appdomain_proto,
+            &QName::new(Namespace::public(), "constructor"),
+            activation,
+        )?
+        .coerce_to_object(activation)?;
+
     if let Some(appdomain) = appdomain {
         return Ok(DomainObject::from_domain(
             activation.context.gc_context,
-            Some(activation.context.avm2.prototypes().application_domain),
+            appdomain_constr,
+            Some(appdomain_proto),
             appdomain,
         )
         .into());
@@ -59,9 +69,19 @@ pub fn parent_domain<'gc>(
 ) -> Result<Value<'gc>, Error> {
     if let Some(appdomain) = this.and_then(|this| this.as_application_domain()) {
         if let Some(parent_domain) = appdomain.parent_domain() {
+            let mut appdomain_proto = activation.avm2().prototypes().application_domain;
+            let appdomain_constr = appdomain_proto
+                .get_property(
+                    appdomain_proto,
+                    &QName::new(Namespace::public(), "constructor"),
+                    activation,
+                )?
+                .coerce_to_object(activation)?;
+
             return Ok(DomainObject::from_domain(
                 activation.context.gc_context,
-                Some(activation.context.avm2.prototypes().application_domain),
+                appdomain_constr,
+                Some(appdomain_proto),
                 parent_domain,
             )
             .into());
diff --git a/core/src/avm2/globals/function.rs b/core/src/avm2/globals/function.rs
index 39bb301ef..f4f577f10 100644
--- a/core/src/avm2/globals/function.rs
+++ b/core/src/avm2/globals/function.rs
@@ -9,7 +9,6 @@ use crate::avm2::object::{ClassObject, FunctionObject, Object, ScriptObject, TOb
 use crate::avm2::scope::Scope;
 use crate::avm2::value::Value;
 use crate::avm2::Error;
-use gc_arena::GcCell;
 
 /// Implements `Function`'s instance initializer.
 pub fn instance_init<'gc>(
@@ -90,12 +89,21 @@ fn apply<'gc>(
 
 /// Create Function prototype.
 ///
-/// This function creates a suitable class and object prototype attached to it.
+/// This function creates a suitable prototype and returns it.
 pub fn create_proto<'gc>(
     activation: &mut Activation<'_, 'gc, '_>,
-    globals: Object<'gc>,
     super_proto: Object<'gc>,
-) -> (Object<'gc>, GcCell<'gc, Class<'gc>>) {
+) -> Object<'gc> {
+    ScriptObject::object(activation.context.gc_context, super_proto)
+}
+
+/// Fill `Function.prototype` and allocate it's constructor.
+pub fn fill_proto<'gc>(
+    activation: &mut Activation<'_, 'gc, '_>,
+    globals: Object<'gc>,
+    mut function_proto: Object<'gc>,
+    super_constr: Object<'gc>,
+) -> Object<'gc> {
     let function_class = Class::new(
         QName::new(Namespace::public(), "Function"),
         Some(QName::new(Namespace::public(), "Object").into()),
@@ -104,22 +112,7 @@ pub fn create_proto<'gc>(
         activation.context.gc_context,
     );
     let scope = Scope::push_scope(globals.get_scope(), globals, activation.context.gc_context);
-    let function_proto = ScriptObject::prototype(
-        activation.context.gc_context,
-        super_proto,
-        function_class,
-        Some(scope),
-    );
 
-    (function_proto, function_class)
-}
-
-/// Fill `Function.prototype` and allocate it's constructor.
-pub fn fill_proto<'gc>(
-    activation: &mut Activation<'_, 'gc, '_>,
-    mut function_proto: Object<'gc>,
-    super_class: Object<'gc>,
-) -> Object<'gc> {
     function_proto.install_method(
         activation.context.gc_context,
         QName::new(Namespace::as3_namespace(), "call"),
@@ -135,7 +128,9 @@ pub fn fill_proto<'gc>(
 
     ClassObject::from_builtin_constr(
         activation.context.gc_context,
-        Some(super_class),
+        Some(super_constr),
+        function_class,
+        Some(scope),
         function_proto,
         function_proto,
     )
diff --git a/core/src/avm2/globals/object.rs b/core/src/avm2/globals/object.rs
index 6e9057083..b43230ee9 100644
--- a/core/src/avm2/globals/object.rs
+++ b/core/src/avm2/globals/object.rs
@@ -9,7 +9,6 @@ use crate::avm2::scope::Scope;
 use crate::avm2::traits::Trait;
 use crate::avm2::value::Value;
 use crate::avm2::Error;
-use gc_arena::GcCell;
 
 /// Implements `Object`'s instance initializer.
 pub fn instance_init<'gc>(
@@ -155,38 +154,8 @@ pub fn set_property_is_enumerable<'gc>(
 /// This function creates a suitable class and object prototype attached to it,
 /// but does not actually fill it with methods. That requires a valid function
 /// prototype, and is thus done by `fill_proto` below.
-pub fn create_proto<'gc>(
-    activation: &mut Activation<'_, 'gc, '_>,
-    globals: Object<'gc>,
-) -> (Object<'gc>, GcCell<'gc, Class<'gc>>) {
-    let object_class = Class::new(
-        QName::new(Namespace::public(), "Object"),
-        None,
-        Method::from_builtin(instance_init),
-        Method::from_builtin(class_init),
-        activation.context.gc_context,
-    );
-    let mut write = object_class.write(activation.context.gc_context);
-
-    write.define_class_trait(Trait::from_const(
-        QName::new(Namespace::public(), "length"),
-        QName::new(Namespace::public(), "int").into(),
-        None,
-    ));
-
-    // Fixed traits (in AS3 namespace)
-    const PUBLIC_INSTANCE_METHODS: &[(&str, NativeMethod)] = &[
-        ("hasOwnProperty", has_own_property),
-        ("isPrototypeOf", is_prototype_of),
-        ("propertyIsEnumerable", property_is_enumerable),
-    ];
-    write.define_as3_builtin_instance_methods(PUBLIC_INSTANCE_METHODS);
-
-    let scope = Scope::push_scope(globals.get_scope(), globals, activation.context.gc_context);
-    let proto =
-        ScriptObject::bare_prototype(activation.context.gc_context, object_class, Some(scope));
-
-    (proto, object_class)
+pub fn create_proto<'gc>(activation: &mut Activation<'_, 'gc, '_>) -> Object<'gc> {
+    ScriptObject::bare_object(activation.context.gc_context)
 }
 
 /// Finish constructing `Object.prototype`, and also construct `Object`.
@@ -200,10 +169,12 @@ pub fn create_proto<'gc>(
 /// bare objects for both and let this function fill Object for you.
 pub fn fill_proto<'gc>(
     activation: &mut Activation<'_, 'gc, '_>,
+    globals: Object<'gc>,
     mut object_proto: Object<'gc>,
     fn_proto: Object<'gc>,
 ) -> Result<Object<'gc>, Error> {
     let gc_context = activation.context.gc_context;
+
     object_proto.install_dynamic_property(
         gc_context,
         QName::new(Namespace::public(), "hasOwnProperty"),
@@ -240,6 +211,39 @@ pub fn fill_proto<'gc>(
         FunctionObject::from_builtin(gc_context, value_of, fn_proto).into(),
     )?;
 
-    let object_constr = ClassObject::from_builtin_constr(gc_context, None, object_proto, fn_proto)?;
-    Ok(object_constr)
+    let object_class = Class::new(
+        QName::new(Namespace::public(), "Object"),
+        None,
+        Method::from_builtin(instance_init),
+        Method::from_builtin(class_init),
+        gc_context,
+    );
+    let mut write = object_class.write(gc_context);
+
+    write.define_class_trait(Trait::from_const(
+        QName::new(Namespace::public(), "length"),
+        QName::new(Namespace::public(), "int").into(),
+        None,
+    ));
+
+    // Fixed traits (in AS3 namespace)
+    const PUBLIC_INSTANCE_METHODS: &[(&str, NativeMethod)] = &[
+        ("hasOwnProperty", has_own_property),
+        ("isPrototypeOf", is_prototype_of),
+        ("propertyIsEnumerable", property_is_enumerable),
+    ];
+    write.define_as3_builtin_instance_methods(PUBLIC_INSTANCE_METHODS);
+
+    drop(write);
+
+    let scope = Scope::push_scope(globals.get_scope(), globals, gc_context);
+
+    ClassObject::from_builtin_constr(
+        gc_context,
+        None,
+        object_class,
+        Some(scope),
+        object_proto,
+        fn_proto,
+    )
 }
diff --git a/core/src/avm2/globals/regexp.rs b/core/src/avm2/globals/regexp.rs
index 09d5fa0cd..8a21ef0fd 100644
--- a/core/src/avm2/globals/regexp.rs
+++ b/core/src/avm2/globals/regexp.rs
@@ -209,15 +209,19 @@ pub fn exec<'gc>(
                 None => return Ok(Value::Null),
             };
 
+            let mut regexp_proto = activation.avm2().prototypes().array;
+            let regexp_constr = regexp_proto
+                .get_property(
+                    regexp_proto,
+                    &QName::new(Namespace::public(), "constructor"),
+                    activation,
+                )?
+                .coerce_to_object(activation)?;
+
             let object = ArrayObject::from_array(
                 storage,
-                activation
-                    .context
-                    .avm2
-                    .system_prototypes
-                    .as_ref()
-                    .map(|sp| sp.array)
-                    .unwrap(),
+                regexp_constr,
+                regexp_proto,
                 activation.context.gc_context,
             );
 
diff --git a/core/src/avm2/object.rs b/core/src/avm2/object.rs
index ee090dad8..7bdbf48d5 100644
--- a/core/src/avm2/object.rs
+++ b/core/src/avm2/object.rs
@@ -113,17 +113,25 @@ pub trait TObject<'gc>: 'gc + Collect + Debug + Into<Object<'gc>> + Clone + Copy
         Ok(Value::Undefined)
     }
 
-    /// Retrieve the base prototype that a particular QName trait is defined in.
+    /// Retrieve the base class constructor that a particular QName trait is
+    /// defined in.
+    ///
+    /// Must be called on a class constructor; will error out if called on
+    /// anything else.
     ///
     /// This function returns `None` for non-trait properties, such as actually
     /// defined prototype methods for ES3-style classes.
-    fn get_base_proto(self, name: &QName<'gc>) -> Result<Option<Object<'gc>>, Error> {
-        if self.provides_trait(name)? {
+    fn find_base_constr_for_trait(self, name: &QName<'gc>) -> Result<Option<Object<'gc>>, Error> {
+        let class = self
+            .as_class()
+            .ok_or("Cannot get base traits on non-class object")?;
+
+        if class.read().has_instance_trait(name) {
             return Ok(Some(self.into()));
         }
 
-        if let Some(proto) = self.proto() {
-            return proto.get_base_proto(name);
+        if let Some(base) = self.base_class_constr() {
+            return base.find_base_constr_for_trait(name);
         }
 
         Ok(None)
@@ -305,26 +313,6 @@ pub trait TObject<'gc>: 'gc + Collect + Debug + Into<Object<'gc>> + Clone + Copy
     /// prototype chain bearing this name is malformed in some way.
     fn get_trait_slot(self, id: u32) -> Result<Option<Trait<'gc>>, Error>;
 
-    /// Populate a list of traits that this object provides for a given name.
-    ///
-    /// This function yields traits for class constructors and prototypes, but
-    /// not instances. For resolving traits for normal `TObject` methods, use
-    /// `get_trait` and `has_trait` as it will tell you if the current object
-    /// has a given trait.
-    fn get_provided_trait(
-        &self,
-        name: &QName<'gc>,
-        known_traits: &mut Vec<Trait<'gc>>,
-    ) -> Result<(), Error>;
-
-    /// Populate a list of traits that this object provides for a given slot.
-    ///
-    /// This function yields traits for class constructors and prototypes, but
-    /// not instances. For resolving traits for normal `TObject` methods, use
-    /// `get_trait` and `has_trait` as it will tell you if the current object
-    /// has a given trait.
-    fn get_provided_trait_slot(&self, id: u32) -> Result<Option<Trait<'gc>>, Error>;
-
     /// Retrieves the scope chain of the object at time of its creation.
     ///
     /// The scope chain is used to determine the starting scope stack when an
@@ -397,11 +385,6 @@ pub trait TObject<'gc>: 'gc + Collect + Debug + Into<Object<'gc>> + Clone + Copy
     /// Returns true if an object has one or more traits of a given name.
     fn has_trait(self, name: &QName<'gc>) -> Result<bool, Error>;
 
-    /// Returns true if an object is part of a class that defines a trait of a
-    /// given name on itself (as opposed to merely inheriting a superclass
-    /// trait.)
-    fn provides_trait(self, name: &QName<'gc>) -> Result<bool, Error>;
-
     /// Indicates whether or not a property or *instantiated* trait exists on
     /// an object and is not part of the prototype chain.
     ///
@@ -732,49 +715,200 @@ pub trait TObject<'gc>: 'gc + Collect + Debug + Into<Object<'gc>> + Clone + Copy
         _reciever: Option<Object<'gc>>,
         _arguments: &[Value<'gc>],
         _activation: &mut Activation<'_, 'gc, '_>,
-        _base_proto: Option<Object<'gc>>,
+        _base_constr: Option<Object<'gc>>,
     ) -> Result<Value<'gc>, Error> {
         Err("Object is not callable".into())
     }
 
-    /// Construct a host object of some kind and return its cell.
+    /// Call an instance method by name.
+    ///
+    /// Intended to be called on the current base constructor used for
+    /// searching for traits. That constructor's base classes will be searched
+    /// for an appropriately named method trait, and if found, the method will
+    /// be called with the given reciever, arguments and new ancestor
+    /// constructor.
+    fn call_instance_method(
+        self,
+        name: &QName<'gc>,
+        reciever: Option<Object<'gc>>,
+        arguments: &[Value<'gc>],
+        activation: &mut Activation<'_, 'gc, '_>,
+    ) -> Result<Value<'gc>, Error> {
+        let constr_with_trait = self.find_base_constr_for_trait(&name)?.ok_or_else(|| {
+            format!(
+                "Attempted to supercall method {:?}, which does not exist",
+                name
+            )
+        })?;
+        let mut class_traits = Vec::new();
+        constr_with_trait
+            .as_class()
+            .unwrap()
+            .read()
+            .lookup_instance_traits(name, &mut class_traits)?;
+        let base_trait = class_traits.first().ok_or_else(|| {
+            format!(
+                "Attempted to supercall method {:?}, which does not exist",
+                name
+            )
+        })?;
+        let scope = constr_with_trait.get_scope();
+
+        if let TraitKind::Method { method, .. } = base_trait.kind() {
+            let callee = FunctionObject::from_method(
+                activation.context.gc_context,
+                method.clone(),
+                scope,
+                activation.avm2().prototypes().function,
+                reciever,
+            );
+
+            callee.call(reciever, arguments, activation, Some(constr_with_trait))
+        } else {
+            Err(format!(
+                "Attempted to supercall method {:?}, which does not exist",
+                name
+            )
+            .into())
+        }
+    }
+
+    /// Call an instance getter by name.
+    ///
+    /// Intended to be called on the current base constructor used for
+    /// searching for traits. That constructor's base classes will be searched
+    /// for an appropriately named getter trait, and if found, the getter will
+    /// be called with the given reciever, arguments and new ancestor
+    /// constructor.
+    fn call_instance_getter(
+        self,
+        name: &QName<'gc>,
+        reciever: Option<Object<'gc>>,
+        activation: &mut Activation<'_, 'gc, '_>,
+    ) -> Result<Value<'gc>, Error> {
+        let constr_with_trait = self.find_base_constr_for_trait(&name)?.ok_or_else(|| {
+            format!(
+                "Attempted to supercall method {:?}, which does not exist",
+                name
+            )
+        })?;
+        let mut class_traits = Vec::new();
+        constr_with_trait
+            .as_class()
+            .unwrap()
+            .read()
+            .lookup_instance_traits(name, &mut class_traits)?;
+        let base_trait = class_traits.first().ok_or_else(|| {
+            format!(
+                "Attempted to supercall method {:?}, which does not exist",
+                name
+            )
+        })?;
+        let scope = constr_with_trait.get_scope();
+
+        if let TraitKind::Getter { method, .. } = base_trait.kind() {
+            let callee = FunctionObject::from_method(
+                activation.context.gc_context,
+                method.clone(),
+                scope,
+                activation.avm2().prototypes().function,
+                reciever,
+            );
+
+            callee.call(reciever, &[], activation, Some(constr_with_trait))
+        } else {
+            Err(format!(
+                "Attempted to supercall getter for {:?}, which does not exist",
+                name
+            )
+            .into())
+        }
+    }
+
+    /// Call an instance setter by name.
+    ///
+    /// Intended to be called on the current base constructor used for
+    /// searching for traits. That constructor's base classes will be searched
+    /// for an appropriately named setter trait, and if found, the setter will
+    /// be called with the given reciever, arguments and new ancestor
+    /// constructor.
+    fn call_instance_setter(
+        self,
+        name: &QName<'gc>,
+        value: Value<'gc>,
+        reciever: Option<Object<'gc>>,
+        activation: &mut Activation<'_, 'gc, '_>,
+    ) -> Result<(), Error> {
+        let constr_with_trait = self.find_base_constr_for_trait(&name)?.ok_or_else(|| {
+            format!(
+                "Attempted to supercall method {:?}, which does not exist",
+                name
+            )
+        })?;
+        let mut class_traits = Vec::new();
+        constr_with_trait
+            .as_class()
+            .unwrap()
+            .read()
+            .lookup_instance_traits(name, &mut class_traits)?;
+        let base_trait = class_traits.first().ok_or_else(|| {
+            format!(
+                "Attempted to supercall method {:?}, which does not exist",
+                name
+            )
+        })?;
+        let scope = constr_with_trait.get_scope();
+
+        if let TraitKind::Setter { method, .. } = base_trait.kind() {
+            let callee = FunctionObject::from_method(
+                activation.context.gc_context,
+                method.clone(),
+                scope,
+                activation.avm2().prototypes().function,
+                reciever,
+            );
+
+            callee.call(reciever, &[value], activation, Some(constr_with_trait))?;
+
+            Ok(())
+        } else {
+            Err(format!(
+                "Attempted to supercall setter for {:?}, which does not exist",
+                name
+            )
+            .into())
+        }
+    }
+
+    /// Construct a Class or Function and return an instance of it.
     ///
     /// As the first step in object construction, the `construct` method is
-    /// called on the prototype to create a new object. The prototype may
-    /// construct any object implementation it wants, however, it's expected
-    /// to produce a like `TObject` implementor with itself as the new object's
-    /// proto.
+    /// called on the constructor to create a new object. The constructor is
+    /// then expected to perform the following steps, in order:
     ///
-    /// After construction, the constructor function is `call`ed with the new
-    /// object as `this` to initialize the object.
-    ///
-    /// `construct`ed objects should instantiate instance traits of the class
-    /// that this prototype represents.
-    ///
-    /// The arguments passed to the constructor are provided here; however, all
-    /// object construction should happen in `call`, not `new`. `new` exists
-    /// purely so that host objects can be constructed by the VM.
+    /// 1. Allocate the instance object. If the constructor is a `Class`, then
+    /// use the class's instance deriver to allocate the object. Otherwise,
+    /// allocate it as the same type as the constructor's explicit `prototype`.
+    /// 2. Associate the instance object with the constructor's explicit
+    /// `prototype`.
+    /// 3. If the instance has traits, install them at this time.
+    /// 4. Call the constructor method with the newly-allocated object as
+    /// reciever. For `Function`s, this is just the function's method.
+    /// 5. Yield the allocated object. (The return values of constructors are
+    /// ignored.)
     fn construct(
-        &self,
-        activation: &mut Activation<'_, 'gc, '_>,
-        args: &[Value<'gc>],
-    ) -> Result<Object<'gc>, Error>;
+        self,
+        _activation: &mut Activation<'_, 'gc, '_>,
+        _args: &[Value<'gc>],
+    ) -> Result<Object<'gc>, Error> {
+        Err("Object is not constructable".into())
+    }
 
     /// Construct a host object prototype of some kind and return it.
     ///
-    /// This is called specifically to construct prototypes. The primary
-    /// difference is that a new class and scope closure are defined here.
-    /// Objects constructed from the new prototype should use that new class
-    /// and scope closure when instantiating non-prototype traits.
-    ///
-    /// Unlike `construct`, `derive`d objects should *not* instantiate instance
-    /// traits.
-    fn derive(
-        &self,
-        activation: &mut Activation<'_, 'gc, '_>,
-        class: GcCell<'gc, Class<'gc>>,
-        scope: Option<GcCell<'gc, Scope<'gc>>>,
-    ) -> Result<Object<'gc>, Error>;
+    /// This is called specifically to allocate old-style ES3 instances. The
+    /// returned object should have no properties upon it.
+    fn derive(&self, activation: &mut Activation<'_, 'gc, '_>) -> Result<Object<'gc>, Error>;
 
     /// Determine the type of primitive coercion this object would prefer, in
     /// the case that there is no obvious reason to prefer one type over the
@@ -796,7 +930,7 @@ pub trait TObject<'gc>: 'gc + Collect + Debug + Into<Object<'gc>> + Clone + Copy
     /// coercions.
     fn to_string(&self, mc: MutationContext<'gc, '_>) -> Result<Value<'gc>, Error> {
         let class_name = self
-            .as_proto_class()
+            .as_class()
             .map(|c| c.read().name().local_name())
             .unwrap_or_else(|| "Object".into());
 
@@ -813,7 +947,7 @@ pub trait TObject<'gc>: 'gc + Collect + Debug + Into<Object<'gc>> + Clone + Copy
     /// of the class that created this object).
     fn to_locale_string(&self, mc: MutationContext<'gc, '_>) -> Result<Value<'gc>, Error> {
         let class_name = self
-            .as_proto_class()
+            .as_class()
             .map(|c| c.read().name().local_name())
             .unwrap_or_else(|| "Object".into());
 
@@ -892,28 +1026,21 @@ pub trait TObject<'gc>: 'gc + Collect + Debug + Into<Object<'gc>> + Clone + Copy
     /// Get this object's `Class`, if it has one.
     fn as_class(&self) -> Option<GcCell<'gc, Class<'gc>>>;
 
+    /// Get this object's constructor, if it has one.
+    fn as_constr(&self) -> Option<Object<'gc>>;
+
+    /// Associate the object with a particular constructor.
+    ///
+    /// This turns the object into an instance of that class. It should only be
+    /// used in situations where the object cannot be made an instance of the
+    /// class at allocation time, such as during early runtime setup.
+    fn set_constr(self, mc: MutationContext<'gc, '_>, constr: Object<'gc>);
+
     /// Get the base class constructor of this object.
     fn base_class_constr(self) -> Option<Object<'gc>> {
         None
     }
 
-    /// Get this object's `Class`, or any `Class` on its prototype chain.
-    ///
-    /// This only yields `None` for bare objects.
-    fn as_proto_class(&self) -> Option<GcCell<'gc, Class<'gc>>> {
-        let mut class = self.as_class();
-
-        while class.is_none() {
-            if let Some(proto) = self.proto() {
-                class = proto.as_class();
-            } else {
-                return None;
-            }
-        }
-
-        class
-    }
-
     /// Get this object's `Executable`, if it has one.
     fn as_executable(&self) -> Option<Executable<'gc>> {
         None
diff --git a/core/src/avm2/object/array_object.rs b/core/src/avm2/object/array_object.rs
index 080cd08a6..a3d2b8fcf 100644
--- a/core/src/avm2/object/array_object.rs
+++ b/core/src/avm2/object/array_object.rs
@@ -17,20 +17,11 @@ use std::cell::{Ref, RefMut};
 
 /// A class instance deriver that constructs array objects.
 pub fn array_deriver<'gc>(
-    mut constr: Object<'gc>,
+    constr: Object<'gc>,
+    proto: Object<'gc>,
     activation: &mut Activation<'_, 'gc, '_>,
-    class: GcCell<'gc, Class<'gc>>,
-    scope: Option<GcCell<'gc, Scope<'gc>>>,
 ) -> Result<Object<'gc>, Error> {
-    let base_proto = constr
-        .get_property(
-            constr,
-            &QName::new(Namespace::public(), "prototype"),
-            activation,
-        )?
-        .coerce_to_object(activation)?;
-
-    ArrayObject::derive(base_proto, activation.context.gc_context, class, scope)
+    ArrayObject::derive(constr, proto, activation.context.gc_context)
 }
 
 /// An Object which stores numerical properties in an array.
@@ -50,8 +41,13 @@ pub struct ArrayObjectData<'gc> {
 
 impl<'gc> ArrayObject<'gc> {
     /// Construct a fresh array.
-    pub fn construct(base_proto: Object<'gc>, mc: MutationContext<'gc, '_>) -> Object<'gc> {
-        let base = ScriptObjectData::base_new(Some(base_proto), ScriptObjectClass::NoClass);
+    pub fn construct(
+        constr: Object<'gc>,
+        proto: Object<'gc>,
+        mc: MutationContext<'gc, '_>,
+    ) -> Object<'gc> {
+        let base =
+            ScriptObjectData::base_new(Some(proto), ScriptObjectClass::ClassInstance(constr));
 
         ArrayObject(GcCell::allocate(
             mc,
@@ -65,15 +61,12 @@ impl<'gc> ArrayObject<'gc> {
 
     /// Construct a primitive subclass.
     pub fn derive(
+        constr: Object<'gc>,
         base_proto: Object<'gc>,
         mc: MutationContext<'gc, '_>,
-        class: GcCell<'gc, Class<'gc>>,
-        scope: Option<GcCell<'gc, Scope<'gc>>>,
     ) -> Result<Object<'gc>, Error> {
-        let base = ScriptObjectData::base_new(
-            Some(base_proto),
-            ScriptObjectClass::InstancePrototype(class, scope),
-        );
+        let base =
+            ScriptObjectData::base_new(Some(base_proto), ScriptObjectClass::ClassInstance(constr));
 
         Ok(ArrayObject(GcCell::allocate(
             mc,
@@ -88,10 +81,12 @@ impl<'gc> ArrayObject<'gc> {
     /// Wrap an existing array in an object.
     pub fn from_array(
         array: ArrayStorage<'gc>,
-        base_proto: Object<'gc>,
+        constr: Object<'gc>,
+        proto: Object<'gc>,
         mc: MutationContext<'gc, '_>,
     ) -> Object<'gc> {
-        let base = ScriptObjectData::base_new(Some(base_proto), ScriptObjectClass::NoClass);
+        let base =
+            ScriptObjectData::base_new(Some(proto), ScriptObjectClass::ClassInstance(constr));
 
         ArrayObject(GcCell::allocate(mc, ArrayObjectData { base, array })).into()
     }
@@ -242,11 +237,7 @@ impl<'gc> TObject<'gc> for ArrayObject<'gc> {
         Some(RefMut::map(self.0.write(mc), |aod| &mut aod.array))
     }
 
-    fn construct(
-        &self,
-        activation: &mut Activation<'_, 'gc, '_>,
-        _args: &[Value<'gc>],
-    ) -> Result<Object<'gc>, Error> {
+    fn derive(&self, activation: &mut Activation<'_, 'gc, '_>) -> Result<Object<'gc>, Error> {
         let this: Object<'gc> = Object::ArrayObject(*self);
         let base = ScriptObjectData::base_new(Some(this), ScriptObjectClass::NoClass);
 
@@ -259,26 +250,4 @@ impl<'gc> TObject<'gc> for ArrayObject<'gc> {
         ))
         .into())
     }
-
-    fn derive(
-        &self,
-        activation: &mut Activation<'_, 'gc, '_>,
-        class: GcCell<'gc, Class<'gc>>,
-        scope: Option<GcCell<'gc, Scope<'gc>>>,
-    ) -> Result<Object<'gc>, Error> {
-        let this: Object<'gc> = Object::ArrayObject(*self);
-        let base = ScriptObjectData::base_new(
-            Some(this),
-            ScriptObjectClass::InstancePrototype(class, scope),
-        );
-
-        Ok(ArrayObject(GcCell::allocate(
-            activation.context.gc_context,
-            ArrayObjectData {
-                base,
-                array: ArrayStorage::new(0),
-            },
-        ))
-        .into())
-    }
 }
diff --git a/core/src/avm2/object/bytearray_object.rs b/core/src/avm2/object/bytearray_object.rs
index 8d94d8b7c..05f0d781f 100644
--- a/core/src/avm2/object/bytearray_object.rs
+++ b/core/src/avm2/object/bytearray_object.rs
@@ -15,20 +15,11 @@ use std::cell::{Ref, RefMut};
 
 /// A class instance deriver that constructs ByteArray objects.
 pub fn bytearray_deriver<'gc>(
-    mut constr: Object<'gc>,
+    constr: Object<'gc>,
+    proto: Object<'gc>,
     activation: &mut Activation<'_, 'gc, '_>,
-    class: GcCell<'gc, Class<'gc>>,
-    scope: Option<GcCell<'gc, Scope<'gc>>>,
 ) -> Result<Object<'gc>, Error> {
-    let base_proto = constr
-        .get_property(
-            constr,
-            &QName::new(Namespace::public(), "prototype"),
-            activation,
-        )?
-        .coerce_to_object(activation)?;
-
-    ByteArrayObject::derive(base_proto, activation.context.gc_context, class, scope)
+    ByteArrayObject::derive(constr, proto, activation.context.gc_context)
 }
 
 #[derive(Clone, Collect, Debug, Copy)]
@@ -47,9 +38,10 @@ pub struct ByteArrayObjectData<'gc> {
 impl<'gc> ByteArrayObject<'gc> {
     pub fn new(
         mc: MutationContext<'gc, '_>,
-        base_proto: Option<Object<'gc>>,
+        constr: Object<'gc>,
+        proto: Option<Object<'gc>>,
     ) -> ByteArrayObject<'gc> {
-        let base = ScriptObjectData::base_new(base_proto, ScriptObjectClass::NoClass);
+        let base = ScriptObjectData::base_new(proto, ScriptObjectClass::ClassInstance(constr));
 
         ByteArrayObject(GcCell::allocate(
             mc,
@@ -60,20 +52,21 @@ impl<'gc> ByteArrayObject<'gc> {
         ))
     }
 
-    pub fn construct(mc: MutationContext<'gc, '_>, base_proto: Option<Object<'gc>>) -> Object<'gc> {
-        Self::new(mc, base_proto).into()
+    pub fn construct(
+        mc: MutationContext<'gc, '_>,
+        constr: Object<'gc>,
+        base_proto: Option<Object<'gc>>,
+    ) -> Object<'gc> {
+        Self::new(mc, constr, base_proto).into()
     }
 
     pub fn derive(
+        constr: Object<'gc>,
         base_proto: Object<'gc>,
         mc: MutationContext<'gc, '_>,
-        class: GcCell<'gc, Class<'gc>>,
-        scope: Option<GcCell<'gc, Scope<'gc>>>,
     ) -> Result<Object<'gc>, Error> {
-        let base = ScriptObjectData::base_new(
-            Some(base_proto),
-            ScriptObjectClass::InstancePrototype(class, scope),
-        );
+        let base =
+            ScriptObjectData::base_new(Some(base_proto), ScriptObjectClass::ClassInstance(constr));
 
         Ok(ByteArrayObject(GcCell::allocate(
             mc,
@@ -219,29 +212,9 @@ impl<'gc> TObject<'gc> for ByteArrayObject<'gc> {
         self.0.read().base.resolve_any_trait(local_name)
     }
 
-    fn construct(
-        &self,
-        activation: &mut Activation<'_, 'gc, '_>,
-        _args: &[Value<'gc>],
-    ) -> Result<Object<'gc>, Error> {
+    fn derive(&self, activation: &mut Activation<'_, 'gc, '_>) -> Result<Object<'gc>, Error> {
         let this: Object<'gc> = Object::ByteArrayObject(*self);
-        Ok(ByteArrayObject::construct(
-            activation.context.gc_context,
-            Some(this),
-        ))
-    }
-
-    fn derive(
-        &self,
-        activation: &mut Activation<'_, 'gc, '_>,
-        class: GcCell<'gc, Class<'gc>>,
-        scope: Option<GcCell<'gc, Scope<'gc>>>,
-    ) -> Result<Object<'gc>, Error> {
-        let this: Object<'gc> = Object::ByteArrayObject(*self);
-        let base = ScriptObjectData::base_new(
-            Some(this),
-            ScriptObjectClass::InstancePrototype(class, scope),
-        );
+        let base = ScriptObjectData::base_new(Some(this), ScriptObjectClass::NoClass);
 
         Ok(ByteArrayObject(GcCell::allocate(
             activation.context.gc_context,
diff --git a/core/src/avm2/object/class_object.rs b/core/src/avm2/object/class_object.rs
index 98f902575..04da202cc 100644
--- a/core/src/avm2/object/class_object.rs
+++ b/core/src/avm2/object/class_object.rs
@@ -58,11 +58,20 @@ impl<'gc> ClassObject<'gc> {
         base_class_constr: Option<Object<'gc>>,
         scope: Option<GcCell<'gc, Scope<'gc>>>,
     ) -> Result<(Object<'gc>, Object<'gc>), Error> {
-        let class_proto = if let Some(base_class_constr) = base_class_constr {
+        //TODO: Class prototypes are *not* instances of their class and should
+        //not be allocated by a deriver, but instead should be regular objects
+        let class_proto = if let Some(mut base_class_constr) = base_class_constr {
+            let base_proto = base_class_constr
+                .get_property(
+                    base_class_constr,
+                    &QName::new(Namespace::public(), "prototype"),
+                    activation,
+                )?
+                .coerce_to_object(activation)?;
             let derive = class.read().instance_deriver();
-            derive(base_class_constr, activation, class, scope)?
+            derive(base_class_constr, base_proto, activation)?
         } else {
-            ScriptObject::bare_prototype(activation.context.gc_context, class, scope)
+            ScriptObject::bare_object(activation.context.gc_context)
         };
 
         ClassObject::from_class_and_proto(activation, class, base_class_constr, class_proto, scope)
@@ -160,14 +169,11 @@ impl<'gc> ClassObject<'gc> {
     pub fn from_builtin_constr(
         mc: MutationContext<'gc, '_>,
         base_class_constr: Option<Object<'gc>>,
+        class: GcCell<'gc, Class<'gc>>,
+        scope: Option<GcCell<'gc, Scope<'gc>>>,
         mut prototype: Object<'gc>,
         fn_proto: Object<'gc>,
     ) -> Result<Object<'gc>, Error> {
-        let scope = prototype.get_scope();
-        let class: Result<_, Error> = prototype
-            .as_class()
-            .ok_or_else(|| "Cannot construct builtin type without a class".into());
-        let class = class?;
         let instance_constr =
             Executable::from_method(class.read().instance_init(), scope, None, mc);
         let mut base: Object<'gc> = ClassObject(GcCell::allocate(
@@ -225,31 +231,38 @@ impl<'gc> TObject<'gc> for ClassObject<'gc> {
         receiver: Option<Object<'gc>>,
         arguments: &[Value<'gc>],
         activation: &mut Activation<'_, 'gc, '_>,
-        base_proto: Option<Object<'gc>>,
+        base_constr: Option<Object<'gc>>,
     ) -> Result<Value<'gc>, Error> {
         let instance_constr = self.0.read().instance_constr;
 
-        instance_constr.exec(receiver, arguments, activation, base_proto, self.into())
+        instance_constr.exec(receiver, arguments, activation, base_constr, self.into())
     }
 
     fn construct(
-        &self,
+        mut self,
         activation: &mut Activation<'_, 'gc, '_>,
-        _args: &[Value<'gc>],
+        arguments: &[Value<'gc>],
     ) -> Result<Object<'gc>, Error> {
-        Ok(ClassObject(GcCell::allocate(
-            activation.context.gc_context,
-            self.0.read().clone(),
-        ))
-        .into())
+        let class = self.as_class().ok_or("Cannot construct classless class!")?;
+        let deriver = class.read().instance_deriver();
+        let constr: Object<'gc> = self.into();
+        let prototype = self
+            .get_property(
+                constr,
+                &QName::new(Namespace::public(), "prototype"),
+                activation,
+            )?
+            .coerce_to_object(activation)?;
+
+        let instance = deriver(constr, prototype, activation)?;
+        let instance_constr = self.0.read().instance_constr;
+
+        instance_constr.exec(Some(instance), arguments, activation, Some(constr), constr)?;
+
+        Ok(instance)
     }
 
-    fn derive(
-        &self,
-        activation: &mut Activation<'_, 'gc, '_>,
-        _class: GcCell<'gc, Class<'gc>>,
-        _scope: Option<GcCell<'gc, Scope<'gc>>>,
-    ) -> Result<Object<'gc>, Error> {
+    fn derive(&self, activation: &mut Activation<'_, 'gc, '_>) -> Result<Object<'gc>, Error> {
         Ok(ClassObject(GcCell::allocate(
             activation.context.gc_context,
             self.0.read().clone(),
diff --git a/core/src/avm2/object/custom_object.rs b/core/src/avm2/object/custom_object.rs
index 5e20482af..6309516a4 100644
--- a/core/src/avm2/object/custom_object.rs
+++ b/core/src/avm2/object/custom_object.rs
@@ -132,18 +132,6 @@ macro_rules! impl_avm2_custom_object {
             self.0.read().$field.get_trait_slot(id)
         }
 
-        fn get_provided_trait(
-            &self,
-            name: &QName<'gc>,
-            known_traits: &mut Vec<Trait<'gc>>,
-        ) -> Result<(), Error> {
-            self.0.read().$field.get_provided_trait(name, known_traits)
-        }
-
-        fn get_provided_trait_slot(&self, id: u32) -> Result<Option<Trait<'gc>>, Error> {
-            self.0.read().$field.get_provided_trait_slot(id)
-        }
-
         fn get_scope(self) -> Option<GcCell<'gc, Scope<'gc>>> {
             self.0.read().$field.get_scope()
         }
@@ -152,10 +140,6 @@ macro_rules! impl_avm2_custom_object {
             self.0.read().$field.has_trait(name)
         }
 
-        fn provides_trait(self, name: &QName<'gc>) -> Result<bool, Error> {
-            self.0.read().$field.provides_trait(name)
-        }
-
         fn has_instantiated_property(self, name: &QName<'gc>) -> bool {
             self.0.read().$field.has_instantiated_property(name)
         }
@@ -204,6 +188,14 @@ macro_rules! impl_avm2_custom_object {
             self.0.read().base.as_class()
         }
 
+        fn as_constr(&self) -> Option<Object<'gc>> {
+            self.0.read().base.as_constr()
+        }
+
+        fn set_constr(self, mc: MutationContext<'gc, '_>, constr: Object<'gc>) {
+            self.0.write(mc).base.set_constr(constr);
+        }
+
         fn install_method(
             &mut self,
             mc: MutationContext<'gc, '_>,
diff --git a/core/src/avm2/object/dispatch_object.rs b/core/src/avm2/object/dispatch_object.rs
index 32896c062..69e25daba 100644
--- a/core/src/avm2/object/dispatch_object.rs
+++ b/core/src/avm2/object/dispatch_object.rs
@@ -75,19 +75,14 @@ impl<'gc> TObject<'gc> for DispatchObject<'gc> {
     impl_avm2_custom_object_properties!(base);
 
     fn construct(
-        &self,
+        self,
         _activation: &mut Activation<'_, 'gc, '_>,
         _args: &[Value<'gc>],
     ) -> Result<Object<'gc>, Error> {
         Err("Cannot construct internal event dispatcher structures.".into())
     }
 
-    fn derive(
-        &self,
-        _activation: &mut Activation<'_, 'gc, '_>,
-        _class: GcCell<'gc, Class<'gc>>,
-        _scope: Option<GcCell<'gc, Scope<'gc>>>,
-    ) -> Result<Object<'gc>, Error> {
+    fn derive(&self, _activation: &mut Activation<'_, 'gc, '_>) -> Result<Object<'gc>, Error> {
         Err("Cannot subclass internal event dispatcher structures.".into())
     }
 
diff --git a/core/src/avm2/object/domain_object.rs b/core/src/avm2/object/domain_object.rs
index d86c36b18..8620e6739 100644
--- a/core/src/avm2/object/domain_object.rs
+++ b/core/src/avm2/object/domain_object.rs
@@ -16,32 +16,20 @@ use gc_arena::{Collect, GcCell, MutationContext};
 
 /// A class instance deriver that constructs AppDomain objects.
 pub fn appdomain_deriver<'gc>(
-    mut constr: Object<'gc>,
+    constr: Object<'gc>,
+    proto: Object<'gc>,
     activation: &mut Activation<'_, 'gc, '_>,
-    class: GcCell<'gc, Class<'gc>>,
-    scope: Option<GcCell<'gc, Scope<'gc>>>,
 ) -> Result<Object<'gc>, Error> {
+    let scope = constr
+        .get_scope()
+        .ok_or("Constructor has an empty scope stack")?;
     let domain = scope
-        .unwrap()
         .read()
         .globals()
         .as_application_domain()
-        .unwrap();
-    let base_proto = constr
-        .get_property(
-            constr,
-            &QName::new(Namespace::public(), "prototype"),
-            activation,
-        )?
-        .coerce_to_object(activation)?;
+        .ok_or("Constructor scope must have an appdomain at the bottom of it's scope stack")?;
 
-    DomainObject::derive(
-        activation.context.gc_context,
-        base_proto,
-        domain,
-        class,
-        scope,
-    )
+    DomainObject::derive(constr, proto, domain, activation.context.gc_context)
 }
 
 #[derive(Clone, Collect, Debug, Copy)]
@@ -59,28 +47,37 @@ pub struct DomainObjectData<'gc> {
 }
 
 impl<'gc> DomainObject<'gc> {
+    /// Create a new domain without association with any class or prototype.
+    ///
+    /// This should only be called during early player runtime initialization.
+    /// It will return a `Domain` with no proto or instance constructor link,
+    /// meaning that you will have to set those yourself.
+    pub fn from_early_domain(mc: MutationContext<'gc, '_>, domain: Domain<'gc>) -> Object<'gc> {
+        let base = ScriptObjectData::base_new(None, ScriptObjectClass::NoClass);
+
+        DomainObject(GcCell::allocate(mc, DomainObjectData { base, domain })).into()
+    }
+
     pub fn from_domain(
         mc: MutationContext<'gc, '_>,
+        constr: Object<'gc>,
         base_proto: Option<Object<'gc>>,
         domain: Domain<'gc>,
     ) -> Object<'gc> {
-        let base = ScriptObjectData::base_new(base_proto, ScriptObjectClass::NoClass);
+        let base = ScriptObjectData::base_new(base_proto, ScriptObjectClass::ClassInstance(constr));
 
         DomainObject(GcCell::allocate(mc, DomainObjectData { base, domain })).into()
     }
 
     /// Construct a primitive subclass.
     pub fn derive(
-        mc: MutationContext<'gc, '_>,
+        constr: Object<'gc>,
         base_proto: Object<'gc>,
         domain: Domain<'gc>,
-        class: GcCell<'gc, Class<'gc>>,
-        scope: Option<GcCell<'gc, Scope<'gc>>>,
+        mc: MutationContext<'gc, '_>,
     ) -> Result<Object<'gc>, Error> {
-        let base = ScriptObjectData::base_new(
-            Some(base_proto),
-            ScriptObjectClass::InstancePrototype(class, scope),
-        );
+        let base =
+            ScriptObjectData::base_new(Some(base_proto), ScriptObjectClass::ClassInstance(constr));
 
         Ok(DomainObject(GcCell::allocate(mc, DomainObjectData { base, domain })).into())
     }
@@ -100,40 +97,19 @@ impl<'gc> TObject<'gc> for DomainObject<'gc> {
         Ok(this.into())
     }
 
-    fn construct(
-        &self,
-        activation: &mut Activation<'_, 'gc, '_>,
-        args: &[Value<'gc>],
-    ) -> Result<Object<'gc>, Error> {
-        let this: Object<'gc> = Object::DomainObject(*self);
-        let parent_domain = if let Some(parent_domain) = args
-            .get(0)
-            .cloned()
-            .unwrap_or(Value::Undefined)
-            .coerce_to_object(activation)?
-            .as_application_domain()
-        {
-            parent_domain
-        } else {
-            activation.context.avm2.global_domain()
-        };
+    fn derive(&self, activation: &mut Activation<'_, 'gc, '_>) -> Result<Object<'gc>, Error> {
+        let mut this: Object<'gc> = Object::DomainObject(*self);
+        let constr = this
+            .get_property(
+                this,
+                &QName::new(Namespace::public(), "constructor"),
+                activation,
+            )?
+            .coerce_to_object(activation)?;
 
         Ok(DomainObject::from_domain(
             activation.context.gc_context,
-            Some(this),
-            Domain::movie_domain(activation.context.gc_context, parent_domain),
-        ))
-    }
-
-    fn derive(
-        &self,
-        activation: &mut Activation<'_, 'gc, '_>,
-        _class: GcCell<'gc, Class<'gc>>,
-        _scope: Option<GcCell<'gc, Scope<'gc>>>,
-    ) -> Result<Object<'gc>, Error> {
-        let this: Object<'gc> = Object::DomainObject(*self);
-        Ok(DomainObject::from_domain(
-            activation.context.gc_context,
+            constr,
             Some(this),
             activation.context.avm2.global_domain(),
         ))
diff --git a/core/src/avm2/object/event_object.rs b/core/src/avm2/object/event_object.rs
index fd5d2a35f..e4234be07 100644
--- a/core/src/avm2/object/event_object.rs
+++ b/core/src/avm2/object/event_object.rs
@@ -17,24 +17,14 @@ use std::cell::{Ref, RefMut};
 
 /// A class instance deriver that constructs Event objects.
 pub fn event_deriver<'gc>(
-    mut constr: Object<'gc>,
+    constr: Object<'gc>,
+    proto: Object<'gc>,
     activation: &mut Activation<'_, 'gc, '_>,
-    class: GcCell<'gc, Class<'gc>>,
-    scope: Option<GcCell<'gc, Scope<'gc>>>,
 ) -> Result<Object<'gc>, Error> {
-    let base_proto = constr
-        .get_property(
-            constr,
-            &QName::new(Namespace::public(), "prototype"),
-            activation,
-        )?
-        .coerce_to_object(activation)?;
-
     Ok(EventObject::derive(
-        base_proto,
+        constr,
+        proto,
         activation.context.gc_context,
-        class,
-        scope,
     ))
 }
 
@@ -56,25 +46,23 @@ impl<'gc> EventObject<'gc> {
     /// Convert a bare event into it's object representation.
     pub fn from_event(
         mc: MutationContext<'gc, '_>,
+        constr: Object<'gc>,
         base_proto: Option<Object<'gc>>,
         event: Event<'gc>,
     ) -> Object<'gc> {
-        let base = ScriptObjectData::base_new(base_proto, ScriptObjectClass::NoClass);
+        let base = ScriptObjectData::base_new(base_proto, ScriptObjectClass::ClassInstance(constr));
 
         EventObject(GcCell::allocate(mc, EventObjectData { base, event })).into()
     }
 
     /// Instantiate an event subclass.
     pub fn derive(
+        constr: Object<'gc>,
         base_proto: Object<'gc>,
         mc: MutationContext<'gc, '_>,
-        class: GcCell<'gc, Class<'gc>>,
-        scope: Option<GcCell<'gc, Scope<'gc>>>,
     ) -> Object<'gc> {
-        let base = ScriptObjectData::base_new(
-            Some(base_proto),
-            ScriptObjectClass::InstancePrototype(class, scope),
-        );
+        let base =
+            ScriptObjectData::base_new(Some(base_proto), ScriptObjectClass::ClassInstance(constr));
 
         EventObject(GcCell::allocate(
             mc,
@@ -91,33 +79,17 @@ impl<'gc> TObject<'gc> for EventObject<'gc> {
     impl_avm2_custom_object!(base);
     impl_avm2_custom_object_properties!(base);
 
-    fn construct(
-        &self,
-        activation: &mut Activation<'_, 'gc, '_>,
-        _args: &[Value<'gc>],
-    ) -> Result<Object<'gc>, Error> {
-        let this: Object<'gc> = Object::EventObject(*self);
-        Ok(EventObject::from_event(
-            activation.context.gc_context,
-            Some(this),
-            Event::new(""),
-        ))
-    }
+    fn derive(&self, activation: &mut Activation<'_, 'gc, '_>) -> Result<Object<'gc>, Error> {
+        let base = ScriptObjectData::base_new(Some((*self).into()), ScriptObjectClass::NoClass);
 
-    fn derive(
-        &self,
-        activation: &mut Activation<'_, 'gc, '_>,
-        class: GcCell<'gc, Class<'gc>>,
-        scope: Option<GcCell<'gc, Scope<'gc>>>,
-    ) -> Result<Object<'gc>, Error> {
-        let this: Object<'gc> = Object::EventObject(*self);
-
-        Ok(Self::derive(
-            this,
+        Ok(EventObject(GcCell::allocate(
             activation.context.gc_context,
-            class,
-            scope,
+            EventObjectData {
+                base,
+                event: Event::new(""),
+            },
         ))
+        .into())
     }
 
     fn value_of(&self, mc: MutationContext<'gc, '_>) -> Result<Value<'gc>, Error> {
diff --git a/core/src/avm2/object/function_object.rs b/core/src/avm2/object/function_object.rs
index 2cd92fc11..f50e47b2c 100644
--- a/core/src/avm2/object/function_object.rs
+++ b/core/src/avm2/object/function_object.rs
@@ -100,20 +100,37 @@ impl<'gc> TObject<'gc> for FunctionObject<'gc> {
         receiver: Option<Object<'gc>>,
         arguments: &[Value<'gc>],
         activation: &mut Activation<'_, 'gc, '_>,
-        base_proto: Option<Object<'gc>>,
+        base_constr: Option<Object<'gc>>,
     ) -> Result<Value<'gc>, Error> {
         if let Some(exec) = &self.0.read().exec {
-            exec.exec(receiver, arguments, activation, base_proto, self.into())
+            exec.exec(receiver, arguments, activation, base_constr, self.into())
         } else {
             Err("Not a callable function!".into())
         }
     }
 
     fn construct(
-        &self,
+        mut self,
         activation: &mut Activation<'_, 'gc, '_>,
-        _args: &[Value<'gc>],
+        arguments: &[Value<'gc>],
     ) -> Result<Object<'gc>, Error> {
+        let constr: Object<'gc> = self.into();
+        let prototype = self
+            .get_property(
+                constr,
+                &QName::new(Namespace::public(), "prototype"),
+                activation,
+            )?
+            .coerce_to_object(activation)?;
+
+        let instance = prototype.derive(activation)?;
+
+        self.call(Some(instance), arguments, activation, None)?;
+
+        Ok(instance)
+    }
+
+    fn derive(&self, activation: &mut Activation<'_, 'gc, '_>) -> Result<Object<'gc>, Error> {
         let this: Object<'gc> = Object::FunctionObject(*self);
         let base = ScriptObjectData::base_new(Some(this), ScriptObjectClass::NoClass);
 
@@ -123,23 +140,4 @@ impl<'gc> TObject<'gc> for FunctionObject<'gc> {
         ))
         .into())
     }
-
-    fn derive(
-        &self,
-        activation: &mut Activation<'_, 'gc, '_>,
-        class: GcCell<'gc, Class<'gc>>,
-        scope: Option<GcCell<'gc, Scope<'gc>>>,
-    ) -> Result<Object<'gc>, Error> {
-        let this: Object<'gc> = Object::FunctionObject(*self);
-        let base = ScriptObjectData::base_new(
-            Some(this),
-            ScriptObjectClass::InstancePrototype(class, scope),
-        );
-
-        Ok(FunctionObject(GcCell::allocate(
-            activation.context.gc_context,
-            FunctionObjectData { base, exec: None },
-        ))
-        .into())
-    }
 }
diff --git a/core/src/avm2/object/loaderinfo_object.rs b/core/src/avm2/object/loaderinfo_object.rs
index 85353375e..5d69c7844 100644
--- a/core/src/avm2/object/loaderinfo_object.rs
+++ b/core/src/avm2/object/loaderinfo_object.rs
@@ -19,20 +19,11 @@ use std::sync::Arc;
 
 /// A class instance deriver that constructs LoaderInfo objects.
 pub fn loaderinfo_deriver<'gc>(
-    mut constr: Object<'gc>,
+    constr: Object<'gc>,
+    proto: Object<'gc>,
     activation: &mut Activation<'_, 'gc, '_>,
-    class: GcCell<'gc, Class<'gc>>,
-    scope: Option<GcCell<'gc, Scope<'gc>>>,
 ) -> Result<Object<'gc>, Error> {
-    let base_proto = constr
-        .get_property(
-            constr,
-            &QName::new(Namespace::public(), "prototype"),
-            activation,
-        )?
-        .coerce_to_object(activation)?;
-
-    LoaderInfoObject::derive(base_proto, activation.context.gc_context, class, scope)
+    LoaderInfoObject::derive(constr, proto, activation.context.gc_context)
 }
 
 /// Represents a thing which can be loaded by a loader.
@@ -73,10 +64,12 @@ impl<'gc> LoaderInfoObject<'gc> {
     pub fn from_movie(
         movie: Arc<SwfMovie>,
         root: DisplayObject<'gc>,
+        constr: Object<'gc>,
         base_proto: Object<'gc>,
         mc: MutationContext<'gc, '_>,
     ) -> Result<Object<'gc>, Error> {
-        let base = ScriptObjectData::base_new(Some(base_proto), ScriptObjectClass::NoClass);
+        let base =
+            ScriptObjectData::base_new(Some(base_proto), ScriptObjectClass::ClassInstance(constr));
         let loaded_stream = Some(LoaderStream::Swf(movie, root));
 
         Ok(LoaderInfoObject(GcCell::allocate(
@@ -90,8 +83,13 @@ impl<'gc> LoaderInfoObject<'gc> {
     }
 
     /// Create a loader info object for the stage.
-    pub fn from_stage(base_proto: Object<'gc>, mc: MutationContext<'gc, '_>) -> Object<'gc> {
-        let base = ScriptObjectData::base_new(Some(base_proto), ScriptObjectClass::NoClass);
+    pub fn from_stage(
+        constr: Object<'gc>,
+        base_proto: Object<'gc>,
+        mc: MutationContext<'gc, '_>,
+    ) -> Object<'gc> {
+        let base =
+            ScriptObjectData::base_new(Some(base_proto), ScriptObjectClass::ClassInstance(constr));
 
         LoaderInfoObject(GcCell::allocate(
             mc,
@@ -105,15 +103,12 @@ impl<'gc> LoaderInfoObject<'gc> {
 
     /// Construct a loader-info subclass.
     pub fn derive(
+        constr: Object<'gc>,
         base_proto: Object<'gc>,
         mc: MutationContext<'gc, '_>,
-        class: GcCell<'gc, Class<'gc>>,
-        scope: Option<GcCell<'gc, Scope<'gc>>>,
     ) -> Result<Object<'gc>, Error> {
-        let base = ScriptObjectData::base_new(
-            Some(base_proto),
-            ScriptObjectClass::InstancePrototype(class, scope),
-        );
+        let base =
+            ScriptObjectData::base_new(Some(base_proto), ScriptObjectClass::ClassInstance(constr));
 
         Ok(LoaderInfoObject(GcCell::allocate(
             mc,
@@ -131,18 +126,14 @@ impl<'gc> TObject<'gc> for LoaderInfoObject<'gc> {
     impl_avm2_custom_object_properties!(base);
 
     fn value_of(&self, mc: MutationContext<'gc, '_>) -> Result<Value<'gc>, Error> {
-        if let Some(class) = self.as_proto_class() {
+        if let Some(class) = self.as_class() {
             Ok(AvmString::new(mc, format!("[object {}]", class.read().name().local_name())).into())
         } else {
             Ok("[object Object]".into())
         }
     }
 
-    fn construct(
-        &self,
-        activation: &mut Activation<'_, 'gc, '_>,
-        _args: &[Value<'gc>],
-    ) -> Result<Object<'gc>, Error> {
+    fn derive(&self, activation: &mut Activation<'_, 'gc, '_>) -> Result<Object<'gc>, Error> {
         let this: Object<'gc> = Object::LoaderInfoObject(*self);
         let base = ScriptObjectData::base_new(Some(this), ScriptObjectClass::NoClass);
 
@@ -156,28 +147,6 @@ impl<'gc> TObject<'gc> for LoaderInfoObject<'gc> {
         .into())
     }
 
-    fn derive(
-        &self,
-        activation: &mut Activation<'_, 'gc, '_>,
-        class: GcCell<'gc, Class<'gc>>,
-        scope: Option<GcCell<'gc, Scope<'gc>>>,
-    ) -> Result<Object<'gc>, Error> {
-        let this: Object<'gc> = Object::LoaderInfoObject(*self);
-        let base = ScriptObjectData::base_new(
-            Some(this),
-            ScriptObjectClass::InstancePrototype(class, scope),
-        );
-
-        Ok(LoaderInfoObject(GcCell::allocate(
-            activation.context.gc_context,
-            LoaderInfoObjectData {
-                base,
-                loaded_stream: None,
-            },
-        ))
-        .into())
-    }
-
     /// Unwrap this object's loader stream
     fn as_loader_stream(&self) -> Option<Ref<LoaderStream<'gc>>> {
         if self.0.read().loaded_stream.is_some() {
diff --git a/core/src/avm2/object/namespace_object.rs b/core/src/avm2/object/namespace_object.rs
index c39ce0f9a..d70118673 100644
--- a/core/src/avm2/object/namespace_object.rs
+++ b/core/src/avm2/object/namespace_object.rs
@@ -16,20 +16,11 @@ use std::cell::Ref;
 
 /// A class instance deriver that constructs namespace objects.
 pub fn namespace_deriver<'gc>(
-    mut constr: Object<'gc>,
+    constr: Object<'gc>,
+    proto: Object<'gc>,
     activation: &mut Activation<'_, 'gc, '_>,
-    class: GcCell<'gc, Class<'gc>>,
-    scope: Option<GcCell<'gc, Scope<'gc>>>,
 ) -> Result<Object<'gc>, Error> {
-    let base_proto = constr
-        .get_property(
-            constr,
-            &QName::new(Namespace::public(), "prototype"),
-            activation,
-        )?
-        .coerce_to_object(activation)?;
-
-    NamespaceObject::derive(base_proto, activation.context.gc_context, class, scope)
+    NamespaceObject::derive(constr, proto, activation.context.gc_context)
 }
 
 /// An Object which represents a boxed namespace name.
@@ -51,10 +42,12 @@ impl<'gc> NamespaceObject<'gc> {
     /// Box a namespace into an object.
     pub fn from_namespace(
         namespace: Namespace<'gc>,
+        constr: Object<'gc>,
         base_proto: Object<'gc>,
         mc: MutationContext<'gc, '_>,
     ) -> Result<Object<'gc>, Error> {
-        let base = ScriptObjectData::base_new(Some(base_proto), ScriptObjectClass::NoClass);
+        let base =
+            ScriptObjectData::base_new(Some(base_proto), ScriptObjectClass::ClassInstance(constr));
 
         Ok(NamespaceObject(GcCell::allocate(
             mc,
@@ -65,15 +58,12 @@ impl<'gc> NamespaceObject<'gc> {
 
     /// Construct a namespace subclass.
     pub fn derive(
+        constr: Object<'gc>,
         base_proto: Object<'gc>,
         mc: MutationContext<'gc, '_>,
-        class: GcCell<'gc, Class<'gc>>,
-        scope: Option<GcCell<'gc, Scope<'gc>>>,
     ) -> Result<Object<'gc>, Error> {
-        let base = ScriptObjectData::base_new(
-            Some(base_proto),
-            ScriptObjectClass::InstancePrototype(class, scope),
-        );
+        let base =
+            ScriptObjectData::base_new(Some(base_proto), ScriptObjectClass::ClassInstance(constr));
 
         Ok(NamespaceObject(GcCell::allocate(
             mc,
@@ -102,11 +92,7 @@ impl<'gc> TObject<'gc> for NamespaceObject<'gc> {
         Some(Ref::map(self.0.read(), |s| &s.namespace))
     }
 
-    fn construct(
-        &self,
-        activation: &mut Activation<'_, 'gc, '_>,
-        _args: &[Value<'gc>],
-    ) -> Result<Object<'gc>, Error> {
+    fn derive(&self, activation: &mut Activation<'_, 'gc, '_>) -> Result<Object<'gc>, Error> {
         let this: Object<'gc> = Object::NamespaceObject(*self);
         let base = ScriptObjectData::base_new(Some(this), ScriptObjectClass::NoClass);
 
@@ -119,26 +105,4 @@ impl<'gc> TObject<'gc> for NamespaceObject<'gc> {
         ))
         .into())
     }
-
-    fn derive(
-        &self,
-        activation: &mut Activation<'_, 'gc, '_>,
-        class: GcCell<'gc, Class<'gc>>,
-        scope: Option<GcCell<'gc, Scope<'gc>>>,
-    ) -> Result<Object<'gc>, Error> {
-        let this: Object<'gc> = Object::NamespaceObject(*self);
-        let base = ScriptObjectData::base_new(
-            Some(this),
-            ScriptObjectClass::InstancePrototype(class, scope),
-        );
-
-        Ok(NamespaceObject(GcCell::allocate(
-            activation.context.gc_context,
-            NamespaceObjectData {
-                base,
-                namespace: Namespace::public(),
-            },
-        ))
-        .into())
-    }
 }
diff --git a/core/src/avm2/object/primitive_object.rs b/core/src/avm2/object/primitive_object.rs
index 9f86d29fe..2288bc432 100644
--- a/core/src/avm2/object/primitive_object.rs
+++ b/core/src/avm2/object/primitive_object.rs
@@ -17,20 +17,11 @@ use gc_arena::{Collect, GcCell, MutationContext};
 
 /// A class instance deriver that constructs primitive objects.
 pub fn primitive_deriver<'gc>(
-    mut constr: Object<'gc>,
+    constr: Object<'gc>,
+    proto: Object<'gc>,
     activation: &mut Activation<'_, 'gc, '_>,
-    class: GcCell<'gc, Class<'gc>>,
-    scope: Option<GcCell<'gc, Scope<'gc>>>,
 ) -> Result<Object<'gc>, Error> {
-    let base_proto = constr
-        .get_property(
-            constr,
-            &QName::new(Namespace::public(), "prototype"),
-            activation,
-        )?
-        .coerce_to_object(activation)?;
-
-    PrimitiveObject::derive(base_proto, activation.context.gc_context, class, scope)
+    PrimitiveObject::derive(constr, proto, activation.context.gc_context)
 }
 
 /// An Object which represents a primitive value of some other kind.
@@ -52,6 +43,7 @@ impl<'gc> PrimitiveObject<'gc> {
     /// Box a primitive into an object.
     pub fn from_primitive(
         primitive: Value<'gc>,
+        constr: Object<'gc>,
         base_proto: Object<'gc>,
         mc: MutationContext<'gc, '_>,
     ) -> Result<Object<'gc>, Error> {
@@ -59,7 +51,8 @@ impl<'gc> PrimitiveObject<'gc> {
             return Err("Attempted to box an object as a primitive".into());
         }
 
-        let base = ScriptObjectData::base_new(Some(base_proto), ScriptObjectClass::NoClass);
+        let base =
+            ScriptObjectData::base_new(Some(base_proto), ScriptObjectClass::ClassInstance(constr));
 
         Ok(PrimitiveObject(GcCell::allocate(
             mc,
@@ -70,15 +63,12 @@ impl<'gc> PrimitiveObject<'gc> {
 
     /// Construct a primitive subclass.
     pub fn derive(
+        constr: Object<'gc>,
         base_proto: Object<'gc>,
         mc: MutationContext<'gc, '_>,
-        class: GcCell<'gc, Class<'gc>>,
-        scope: Option<GcCell<'gc, Scope<'gc>>>,
     ) -> Result<Object<'gc>, Error> {
-        let base = ScriptObjectData::base_new(
-            Some(base_proto),
-            ScriptObjectClass::InstancePrototype(class, scope),
-        );
+        let base =
+            ScriptObjectData::base_new(Some(base_proto), ScriptObjectClass::ClassInstance(constr));
 
         Ok(PrimitiveObject(GcCell::allocate(
             mc,
@@ -104,7 +94,7 @@ impl<'gc> TObject<'gc> for PrimitiveObject<'gc> {
             val @ Value::Integer(_) | val @ Value::Unsigned(_) => Ok(val),
             _ => {
                 let class_name = self
-                    .as_proto_class()
+                    .as_class()
                     .map(|c| c.read().name().local_name())
                     .unwrap_or_else(|| "Object".into());
 
@@ -117,11 +107,7 @@ impl<'gc> TObject<'gc> for PrimitiveObject<'gc> {
         Ok(self.0.read().primitive.clone())
     }
 
-    fn construct(
-        &self,
-        activation: &mut Activation<'_, 'gc, '_>,
-        _args: &[Value<'gc>],
-    ) -> Result<Object<'gc>, Error> {
+    fn derive(&self, activation: &mut Activation<'_, 'gc, '_>) -> Result<Object<'gc>, Error> {
         let this: Object<'gc> = Object::PrimitiveObject(*self);
         let base = ScriptObjectData::base_new(Some(this), ScriptObjectClass::NoClass);
 
@@ -135,28 +121,6 @@ impl<'gc> TObject<'gc> for PrimitiveObject<'gc> {
         .into())
     }
 
-    fn derive(
-        &self,
-        activation: &mut Activation<'_, 'gc, '_>,
-        class: GcCell<'gc, Class<'gc>>,
-        scope: Option<GcCell<'gc, Scope<'gc>>>,
-    ) -> Result<Object<'gc>, Error> {
-        let this: Object<'gc> = Object::PrimitiveObject(*self);
-        let base = ScriptObjectData::base_new(
-            Some(this),
-            ScriptObjectClass::InstancePrototype(class, scope),
-        );
-
-        Ok(PrimitiveObject(GcCell::allocate(
-            activation.context.gc_context,
-            PrimitiveObjectData {
-                base,
-                primitive: Value::Undefined,
-            },
-        ))
-        .into())
-    }
-
     fn as_primitive_mut(&self, mc: MutationContext<'gc, '_>) -> Option<RefMut<Value<'gc>>> {
         Some(RefMut::map(self.0.write(mc), |pod| &mut pod.primitive))
     }
diff --git a/core/src/avm2/object/regexp_object.rs b/core/src/avm2/object/regexp_object.rs
index c46dcdfb6..779c59d46 100644
--- a/core/src/avm2/object/regexp_object.rs
+++ b/core/src/avm2/object/regexp_object.rs
@@ -17,24 +17,14 @@ use std::cell::{Ref, RefMut};
 
 /// A class instance deriver that constructs RegExp objects.
 pub fn regexp_deriver<'gc>(
-    mut constr: Object<'gc>,
+    constr: Object<'gc>,
+    proto: Object<'gc>,
     activation: &mut Activation<'_, 'gc, '_>,
-    class: GcCell<'gc, Class<'gc>>,
-    scope: Option<GcCell<'gc, Scope<'gc>>>,
 ) -> Result<Object<'gc>, Error> {
-    let base_proto = constr
-        .get_property(
-            constr,
-            &QName::new(Namespace::public(), "prototype"),
-            activation,
-        )?
-        .coerce_to_object(activation)?;
-
     Ok(RegExpObject::derive(
-        base_proto,
+        constr,
+        proto,
         activation.context.gc_context,
-        class,
-        scope,
     ))
 }
 
@@ -54,25 +44,23 @@ pub struct RegExpObjectData<'gc> {
 impl<'gc> RegExpObject<'gc> {
     pub fn from_regexp(
         mc: MutationContext<'gc, '_>,
+        constr: Object<'gc>,
         base_proto: Option<Object<'gc>>,
         regexp: RegExp<'gc>,
     ) -> Object<'gc> {
-        let base = ScriptObjectData::base_new(base_proto, ScriptObjectClass::NoClass);
+        let base = ScriptObjectData::base_new(base_proto, ScriptObjectClass::ClassInstance(constr));
 
         RegExpObject(GcCell::allocate(mc, RegExpObjectData { base, regexp })).into()
     }
 
     /// Instantiate a regexp subclass.
     pub fn derive(
+        constr: Object<'gc>,
         base_proto: Object<'gc>,
         mc: MutationContext<'gc, '_>,
-        class: GcCell<'gc, Class<'gc>>,
-        scope: Option<GcCell<'gc, Scope<'gc>>>,
     ) -> Object<'gc> {
-        let base = ScriptObjectData::base_new(
-            Some(base_proto),
-            ScriptObjectClass::InstancePrototype(class, scope),
-        );
+        let base =
+            ScriptObjectData::base_new(Some(base_proto), ScriptObjectClass::ClassInstance(constr));
 
         RegExpObject(GcCell::allocate(
             mc,
@@ -89,32 +77,17 @@ impl<'gc> TObject<'gc> for RegExpObject<'gc> {
     impl_avm2_custom_object!(base);
     impl_avm2_custom_object_properties!(base);
 
-    fn construct(
-        &self,
-        activation: &mut Activation<'_, 'gc, '_>,
-        _args: &[Value<'gc>],
-    ) -> Result<Object<'gc>, Error> {
-        let this: Object<'gc> = Object::RegExpObject(*self);
-        Ok(RegExpObject::from_regexp(
-            activation.context.gc_context,
-            Some(this),
-            RegExp::new(""),
-        ))
-    }
+    fn derive(&self, activation: &mut Activation<'_, 'gc, '_>) -> Result<Object<'gc>, Error> {
+        let base = ScriptObjectData::base_new(Some((*self).into()), ScriptObjectClass::NoClass);
 
-    fn derive(
-        &self,
-        activation: &mut Activation<'_, 'gc, '_>,
-        class: GcCell<'gc, Class<'gc>>,
-        scope: Option<GcCell<'gc, Scope<'gc>>>,
-    ) -> Result<Object<'gc>, Error> {
-        let this: Object<'gc> = Object::RegExpObject(*self);
-        Ok(Self::derive(
-            this,
+        Ok(RegExpObject(GcCell::allocate(
             activation.context.gc_context,
-            class,
-            scope,
+            RegExpObjectData {
+                base,
+                regexp: RegExp::new(""),
+            },
         ))
+        .into())
     }
 
     fn to_string(&self, _mc: MutationContext<'gc, '_>) -> Result<Value<'gc>, Error> {
diff --git a/core/src/avm2/object/script_object.rs b/core/src/avm2/object/script_object.rs
index 6f602446f..2a66c8812 100644
--- a/core/src/avm2/object/script_object.rs
+++ b/core/src/avm2/object/script_object.rs
@@ -33,12 +33,12 @@ pub struct ScriptObject<'gc>(GcCell<'gc, ScriptObjectData<'gc>>);
 #[derive(Clone, Collect, Debug)]
 #[collect(no_drop)]
 pub enum ScriptObjectClass<'gc> {
-    /// Instantiate instance traits, for prototypes.
-    InstancePrototype(GcCell<'gc, Class<'gc>>, Option<GcCell<'gc, Scope<'gc>>>),
-
     /// Instantiate class traits, for class constructors.
     ClassConstructor(GcCell<'gc, Class<'gc>>, Option<GcCell<'gc, Scope<'gc>>>),
 
+    /// Instantiate instance traits, for class instances.
+    ClassInstance(Object<'gc>),
+
     /// Do not instantiate any class or instance traits.
     NoClass,
 }
@@ -172,18 +172,6 @@ impl<'gc> TObject<'gc> for ScriptObject<'gc> {
         self.0.read().get_trait_slot(id)
     }
 
-    fn get_provided_trait(
-        &self,
-        name: &QName<'gc>,
-        known_traits: &mut Vec<Trait<'gc>>,
-    ) -> Result<(), Error> {
-        self.0.read().get_provided_trait(name, known_traits)
-    }
-
-    fn get_provided_trait_slot(&self, id: u32) -> Result<Option<Trait<'gc>>, Error> {
-        self.0.read().get_provided_trait_slot(id)
-    }
-
     fn get_scope(self) -> Option<GcCell<'gc, Scope<'gc>>> {
         self.0.read().get_scope()
     }
@@ -207,10 +195,6 @@ impl<'gc> TObject<'gc> for ScriptObject<'gc> {
         self.0.read().has_trait(name)
     }
 
-    fn provides_trait(self, name: &QName<'gc>) -> Result<bool, Error> {
-        self.0.read().provides_trait(name)
-    }
-
     fn has_instantiated_property(self, name: &QName<'gc>) -> bool {
         self.0.read().has_instantiated_property(name)
     }
@@ -254,32 +238,13 @@ impl<'gc> TObject<'gc> for ScriptObject<'gc> {
         self.0.as_ptr() as *const ObjectPtr
     }
 
-    fn construct(
-        &self,
-        activation: &mut Activation<'_, 'gc, '_>,
-        _args: &[Value<'gc>],
-    ) -> Result<Object<'gc>, Error> {
+    fn derive(&self, activation: &mut Activation<'_, 'gc, '_>) -> Result<Object<'gc>, Error> {
         let this: Object<'gc> = Object::ScriptObject(*self);
         Ok(ScriptObject::object(activation.context.gc_context, this))
     }
 
-    fn derive(
-        &self,
-        activation: &mut Activation<'_, 'gc, '_>,
-        class: GcCell<'gc, Class<'gc>>,
-        scope: Option<GcCell<'gc, Scope<'gc>>>,
-    ) -> Result<Object<'gc>, Error> {
-        let this: Object<'gc> = Object::ScriptObject(*self);
-        Ok(ScriptObject::prototype(
-            activation.context.gc_context,
-            this,
-            class,
-            scope,
-        ))
-    }
-
     fn to_string(&self, mc: MutationContext<'gc, '_>) -> Result<Value<'gc>, Error> {
-        if let Some(class) = self.as_proto_class() {
+        if let Some(class) = self.as_class() {
             Ok(AvmString::new(mc, format!("[object {}]", class.read().name().local_name())).into())
         } else {
             Ok("[object Object]".into())
@@ -360,6 +325,14 @@ impl<'gc> TObject<'gc> for ScriptObject<'gc> {
     fn as_class(&self) -> Option<GcCell<'gc, Class<'gc>>> {
         self.0.read().as_class()
     }
+
+    fn as_constr(&self) -> Option<Object<'gc>> {
+        self.0.read().as_constr()
+    }
+
+    fn set_constr(self, mc: MutationContext<'gc, '_>, constr: Object<'gc>) {
+        self.0.write(mc).set_constr(constr);
+    }
 }
 
 impl<'gc> ScriptObject<'gc> {
@@ -375,26 +348,6 @@ impl<'gc> ScriptObject<'gc> {
         .into()
     }
 
-    /// Construct a bare class prototype with no base class.
-    ///
-    /// This is used in cases where a prototype needs to exist, but it does not
-    /// need to extend `Object`. This is the case for interfaces and activation
-    /// objects, both of which need to participate in the class mechanism but
-    /// are not `Object`s.
-    pub fn bare_prototype(
-        mc: MutationContext<'gc, '_>,
-        class: GcCell<'gc, Class<'gc>>,
-        scope: Option<GcCell<'gc, Scope<'gc>>>,
-    ) -> Object<'gc> {
-        let script_class = ScriptObjectClass::InstancePrototype(class, scope);
-
-        ScriptObject(GcCell::allocate(
-            mc,
-            ScriptObjectData::base_new(None, script_class),
-        ))
-        .into()
-    }
-
     /// Construct an object with a prototype.
     pub fn object(mc: MutationContext<'gc, '_>, proto: Object<'gc>) -> Object<'gc> {
         ScriptObject(GcCell::allocate(
@@ -404,18 +357,15 @@ impl<'gc> ScriptObject<'gc> {
         .into()
     }
 
-    /// Construct a prototype for an ES4 class.
-    pub fn prototype(
+    /// Construct an instance with a class and scope stack.
+    pub fn instance(
         mc: MutationContext<'gc, '_>,
+        constr: Object<'gc>,
         proto: Object<'gc>,
-        class: GcCell<'gc, Class<'gc>>,
-        scope: Option<GcCell<'gc, Scope<'gc>>>,
     ) -> Object<'gc> {
-        let script_class = ScriptObjectClass::InstancePrototype(class, scope);
-
         ScriptObject(GcCell::allocate(
             mc,
-            ScriptObjectData::base_new(Some(proto), script_class),
+            ScriptObjectData::base_new(Some(proto), ScriptObjectClass::ClassInstance(constr)),
         ))
         .into()
     }
@@ -443,7 +393,15 @@ impl<'gc> ScriptObjectData<'gc> {
         let prop = self.values.get(name);
 
         if let Some(prop) = prop {
-            prop.get(receiver, activation.base_proto().or(self.proto))
+            prop.get(
+                receiver,
+                Some(
+                    activation
+                        .base_constr()
+                        .or_else(|| self.as_constr())
+                        .unwrap_or(receiver),
+                ),
+            )
         } else {
             Ok(Value::Undefined.into())
         }
@@ -456,6 +414,7 @@ impl<'gc> ScriptObjectData<'gc> {
         value: Value<'gc>,
         activation: &mut Activation<'_, 'gc, '_>,
     ) -> Result<ReturnValue<'gc>, Error> {
+        let constr = self.as_constr();
         let slot_id = if let Some(prop) = self.values.get(name) {
             if let Some(slot_id) = prop.slot_id() {
                 Some(slot_id)
@@ -473,8 +432,11 @@ impl<'gc> ScriptObjectData<'gc> {
             Ok(Value::Undefined.into())
         } else if self.values.contains_key(name) {
             let prop = self.values.get_mut(name).unwrap();
-            let proto = self.proto;
-            prop.set(receiver, activation.base_proto().or(proto), value)
+            prop.set(
+                receiver,
+                Some(activation.base_constr().or(constr).unwrap_or(receiver)),
+                value,
+            )
         } else {
             //TODO: Not all classes are dynamic like this
             self.enumerants.push(name.clone());
@@ -492,6 +454,7 @@ impl<'gc> ScriptObjectData<'gc> {
         value: Value<'gc>,
         activation: &mut Activation<'_, 'gc, '_>,
     ) -> Result<ReturnValue<'gc>, Error> {
+        let constr = self.as_constr();
         if let Some(prop) = self.values.get_mut(name) {
             if let Some(slot_id) = prop.slot_id() {
                 // This doesn't need the non-local version of this property
@@ -500,8 +463,11 @@ impl<'gc> ScriptObjectData<'gc> {
                 self.init_slot_local(slot_id, value, activation.context.gc_context)?;
                 Ok(Value::Undefined.into())
             } else {
-                let proto = self.proto;
-                prop.init(receiver, activation.base_proto().or(proto), value)
+                prop.init(
+                    receiver,
+                    Some(activation.base_constr().or(constr).unwrap_or(receiver)),
+                    value,
+                )
             }
         } else {
             //TODO: Not all classes are dynamic like this
@@ -584,89 +550,67 @@ impl<'gc> ScriptObjectData<'gc> {
     pub fn get_trait(&self, name: &QName<'gc>) -> Result<Vec<Trait<'gc>>, Error> {
         match &self.class {
             //Class constructors have local traits only.
-            ScriptObjectClass::ClassConstructor(..) => {
+            ScriptObjectClass::ClassConstructor(class, ..) => {
                 let mut known_traits = Vec::new();
-                self.get_provided_trait(name, &mut known_traits)?;
+                class.read().lookup_class_traits(name, &mut known_traits)?;
 
                 Ok(known_traits)
             }
 
-            //Prototypes do not have traits available locally, but they provide
-            //traits instead.
-            ScriptObjectClass::InstancePrototype(..) => Ok(Vec::new()),
+            //Class instances have all instance traits from all superclasses.
+            ScriptObjectClass::ClassInstance(constr) => {
+                let mut constr_list = Vec::new();
+                let mut cur_constr = Some(*constr);
+                while let Some(constr) = cur_constr {
+                    constr_list.push(constr);
 
-            //Instances walk the prototype chain to build a list of known
-            //traits provided by the classes attached to those prototypes.
-            ScriptObjectClass::NoClass => {
-                let mut known_traits = Vec::new();
-                let mut chain = Vec::new();
-                let mut proto = self.proto();
-
-                while let Some(p) = proto {
-                    chain.push(p);
-                    proto = p.proto();
+                    cur_constr = constr.base_class_constr();
                 }
 
-                for proto in chain.iter().rev() {
-                    proto.get_provided_trait(name, &mut known_traits)?;
+                let mut known_traits = Vec::new();
+                for constr in constr_list.iter().rev() {
+                    let cur_class = constr
+                        .as_class()
+                        .ok_or("Object is not a class constructor")?;
+                    cur_class
+                        .read()
+                        .lookup_instance_traits(name, &mut known_traits)?;
                 }
 
                 Ok(known_traits)
             }
+
+            // Bare objects, ES3 objects, and prototypes do not have traits.
+            ScriptObjectClass::NoClass => Ok(Vec::new()),
         }
     }
 
     pub fn get_trait_slot(&self, id: u32) -> Result<Option<Trait<'gc>>, Error> {
         match &self.class {
             //Class constructors have local slot traits only.
-            ScriptObjectClass::ClassConstructor(..) => self.get_provided_trait_slot(id),
+            ScriptObjectClass::ClassConstructor(class, ..) => {
+                class.read().lookup_class_traits_by_slot(id)
+            }
 
-            //Prototypes do not have traits available locally, but they provide
-            //traits instead.
-            ScriptObjectClass::InstancePrototype(..) => Ok(None),
+            //Class instances have all instance slot traits from all superclasses.
+            ScriptObjectClass::ClassInstance(constr) => {
+                let mut cur_constr = Some(*constr);
 
-            //Instances walk the prototype chain to build a list of known
-            //traits provided by the classes attached to those prototypes.
-            ScriptObjectClass::NoClass => {
-                let mut proto = self.proto();
-
-                while let Some(p) = proto {
-                    if let Some(trait_val) = p.get_provided_trait_slot(id)? {
-                        return Ok(Some(trait_val));
+                while let Some(constr) = cur_constr {
+                    let cur_class = constr
+                        .as_class()
+                        .ok_or("Object is not a class constructor")?;
+                    if let Some(inst_trait) = cur_class.read().lookup_instance_traits_by_slot(id)? {
+                        return Ok(Some(inst_trait));
                     }
 
-                    proto = p.proto();
+                    cur_constr = constr.base_class_constr();
                 }
 
                 Ok(None)
             }
-        }
-    }
 
-    pub fn get_provided_trait(
-        &self,
-        name: &QName<'gc>,
-        known_traits: &mut Vec<Trait<'gc>>,
-    ) -> Result<(), Error> {
-        match &self.class {
-            ScriptObjectClass::ClassConstructor(class, ..) => {
-                class.read().lookup_class_traits(name, known_traits)
-            }
-            ScriptObjectClass::InstancePrototype(class, ..) => {
-                class.read().lookup_instance_traits(name, known_traits)
-            }
-            ScriptObjectClass::NoClass => Ok(()),
-        }
-    }
-
-    pub fn get_provided_trait_slot(&self, id: u32) -> Result<Option<Trait<'gc>>, Error> {
-        match &self.class {
-            ScriptObjectClass::ClassConstructor(class, ..) => {
-                class.read().lookup_class_traits_by_slot(id)
-            }
-            ScriptObjectClass::InstancePrototype(class, ..) => {
-                class.read().lookup_instance_traits_by_slot(id)
-            }
+            // Bare objects, ES3 objects, and prototypes do not have traits.
             ScriptObjectClass::NoClass => Ok(None),
         }
     }
@@ -674,38 +618,30 @@ impl<'gc> ScriptObjectData<'gc> {
     pub fn has_trait(&self, name: &QName<'gc>) -> Result<bool, Error> {
         match &self.class {
             //Class constructors have local traits only.
-            ScriptObjectClass::ClassConstructor(..) => self.provides_trait(name),
+            ScriptObjectClass::ClassConstructor(class, ..) => {
+                Ok(class.read().has_class_trait(name))
+            }
 
-            //Prototypes do not have traits available locally, but we walk
-            //through them to find traits (see `provides_trait`)
-            ScriptObjectClass::InstancePrototype(..) => Ok(false),
+            //Class instances have instance traits from any class in the base
+            //class chain.
+            ScriptObjectClass::ClassInstance(constr) => {
+                let mut cur_constr = Some(*constr);
 
-            //Instances walk the prototype chain to build a list of known
-            //traits provided by the classes attached to those prototypes.
-            ScriptObjectClass::NoClass => {
-                let mut proto = self.proto();
-
-                while let Some(p) = proto {
-                    if p.provides_trait(name)? {
+                while let Some(constr) = cur_constr {
+                    let cur_class = constr
+                        .as_class()
+                        .ok_or("Object is not a class constructor")?;
+                    if cur_class.read().has_instance_trait(name) {
                         return Ok(true);
                     }
 
-                    proto = p.proto();
+                    cur_constr = constr.base_class_constr();
                 }
 
                 Ok(false)
             }
-        }
-    }
 
-    pub fn provides_trait(&self, name: &QName<'gc>) -> Result<bool, Error> {
-        match &self.class {
-            ScriptObjectClass::ClassConstructor(class, ..) => {
-                Ok(class.read().has_class_trait(name))
-            }
-            ScriptObjectClass::InstancePrototype(class, ..) => {
-                Ok(class.read().has_instance_trait(name))
-            }
+            // Bare objects, ES3 objects, and prototypes do not have traits.
             ScriptObjectClass::NoClass => Ok(false),
         }
     }
@@ -713,8 +649,8 @@ impl<'gc> ScriptObjectData<'gc> {
     pub fn get_scope(&self) -> Option<GcCell<'gc, Scope<'gc>>> {
         match &self.class {
             ScriptObjectClass::ClassConstructor(_class, scope) => *scope,
-            ScriptObjectClass::InstancePrototype(_class, scope) => *scope,
-            ScriptObjectClass::NoClass => self.proto().and_then(|proto| proto.get_scope()),
+            ScriptObjectClass::ClassInstance(constr) => constr.get_scope(),
+            ScriptObjectClass::NoClass => None,
         }
     }
 
@@ -725,11 +661,7 @@ impl<'gc> ScriptObjectData<'gc> {
             }
         }
 
-        let trait_ns = match self.class {
-            ScriptObjectClass::ClassConstructor(..) => self.resolve_any_trait(local_name)?,
-            ScriptObjectClass::NoClass => self.resolve_any_trait(local_name)?,
-            _ => None,
-        };
+        let trait_ns = self.resolve_any_trait(local_name)?;
 
         if trait_ns.is_none() {
             if let Some(proto) = self.proto() {
@@ -757,8 +689,21 @@ impl<'gc> ScriptObjectData<'gc> {
             ScriptObjectClass::ClassConstructor(class, ..) => {
                 Ok(class.read().resolve_any_class_trait(local_name))
             }
-            ScriptObjectClass::InstancePrototype(class, ..) => {
-                Ok(class.read().resolve_any_instance_trait(local_name))
+            ScriptObjectClass::ClassInstance(constr) => {
+                let mut cur_constr = Some(*constr);
+
+                while let Some(constr) = cur_constr {
+                    let cur_class = constr
+                        .as_class()
+                        .ok_or("Object is not a class constructor")?;
+                    if let Some(ns) = cur_class.read().resolve_any_instance_trait(local_name) {
+                        return Ok(Some(ns));
+                    }
+
+                    cur_constr = constr.base_class_constr();
+                }
+
+                Ok(None)
             }
             ScriptObjectClass::NoClass => Ok(None),
         }
@@ -989,8 +934,26 @@ impl<'gc> ScriptObjectData<'gc> {
     pub fn as_class(&self) -> Option<GcCell<'gc, Class<'gc>>> {
         match self.class {
             ScriptObjectClass::ClassConstructor(class, _) => Some(class),
-            ScriptObjectClass::InstancePrototype(class, _) => Some(class),
+            ScriptObjectClass::ClassInstance(constr) => constr.as_class(),
             ScriptObjectClass::NoClass => None,
         }
     }
+
+    /// Get the class constructor for this object, if it has one.
+    pub fn as_constr(&self) -> Option<Object<'gc>> {
+        match self.class {
+            ScriptObjectClass::ClassConstructor(..) => None,
+            ScriptObjectClass::ClassInstance(constr) => Some(constr),
+            ScriptObjectClass::NoClass => None,
+        }
+    }
+
+    /// Associate the object with a particular constructor.
+    ///
+    /// This turns the object into an instance of that class. It should only be
+    /// used in situations where the object cannot be made an instance of the
+    /// class at allocation time, such as during early runtime setup.
+    pub fn set_constr(&mut self, constr: Object<'gc>) {
+        self.class = ScriptObjectClass::ClassInstance(constr);
+    }
 }
diff --git a/core/src/avm2/object/stage_object.rs b/core/src/avm2/object/stage_object.rs
index 791f4ff23..22f7ab31a 100644
--- a/core/src/avm2/object/stage_object.rs
+++ b/core/src/avm2/object/stage_object.rs
@@ -16,20 +16,11 @@ use gc_arena::{Collect, GcCell, MutationContext};
 
 /// A class instance deriver that constructs Stage objects.
 pub fn stage_deriver<'gc>(
-    mut constr: Object<'gc>,
+    constr: Object<'gc>,
+    proto: Object<'gc>,
     activation: &mut Activation<'_, 'gc, '_>,
-    class: GcCell<'gc, Class<'gc>>,
-    scope: Option<GcCell<'gc, Scope<'gc>>>,
 ) -> Result<Object<'gc>, Error> {
-    let base_proto = constr
-        .get_property(
-            constr,
-            &QName::new(Namespace::public(), "prototype"),
-            activation,
-        )?
-        .coerce_to_object(activation)?;
-
-    StageObject::derive(base_proto, activation.context.gc_context, class, scope)
+    StageObject::derive(constr, proto, activation.context.gc_context)
 }
 
 #[derive(Clone, Collect, Debug, Copy)]
@@ -50,12 +41,16 @@ impl<'gc> StageObject<'gc> {
     pub fn for_display_object(
         mc: MutationContext<'gc, '_>,
         display_object: DisplayObject<'gc>,
+        constr: Object<'gc>,
         proto: Object<'gc>,
     ) -> Self {
         Self(GcCell::allocate(
             mc,
             StageObjectData {
-                base: ScriptObjectData::base_new(Some(proto), ScriptObjectClass::NoClass),
+                base: ScriptObjectData::base_new(
+                    Some(proto),
+                    ScriptObjectClass::ClassInstance(constr),
+                ),
                 display_object: Some(display_object),
             },
         ))
@@ -63,15 +58,12 @@ impl<'gc> StageObject<'gc> {
 
     /// Construct a stage object subclass.
     pub fn derive(
-        base_proto: Object<'gc>,
+        constr: Object<'gc>,
+        proto: Object<'gc>,
         mc: MutationContext<'gc, '_>,
-        class: GcCell<'gc, Class<'gc>>,
-        scope: Option<GcCell<'gc, Scope<'gc>>>,
     ) -> Result<Object<'gc>, Error> {
-        let base = ScriptObjectData::base_new(
-            Some(base_proto),
-            ScriptObjectClass::InstancePrototype(class, scope),
-        );
+        let base =
+            ScriptObjectData::base_new(Some(proto), ScriptObjectClass::ClassInstance(constr));
 
         Ok(StageObject(GcCell::allocate(
             mc,
@@ -191,18 +183,6 @@ impl<'gc> TObject<'gc> for StageObject<'gc> {
         self.0.read().base.get_trait_slot(id)
     }
 
-    fn get_provided_trait(
-        &self,
-        name: &QName<'gc>,
-        known_traits: &mut Vec<Trait<'gc>>,
-    ) -> Result<(), Error> {
-        self.0.read().base.get_provided_trait(name, known_traits)
-    }
-
-    fn get_provided_trait_slot(&self, id: u32) -> Result<Option<Trait<'gc>>, Error> {
-        self.0.read().base.get_provided_trait_slot(id)
-    }
-
     fn get_scope(self) -> Option<GcCell<'gc, Scope<'gc>>> {
         self.0.read().base.get_scope()
     }
@@ -226,10 +206,6 @@ impl<'gc> TObject<'gc> for StageObject<'gc> {
         self.0.read().base.has_trait(name)
     }
 
-    fn provides_trait(self, name: &QName<'gc>) -> Result<bool, Error> {
-        self.0.read().base.provides_trait(name)
-    }
-
     fn has_instantiated_property(self, name: &QName<'gc>) -> bool {
         self.0.read().base.has_instantiated_property(name)
     }
@@ -282,6 +258,14 @@ impl<'gc> TObject<'gc> for StageObject<'gc> {
         self.0.read().base.as_class()
     }
 
+    fn as_constr(&self) -> Option<Object<'gc>> {
+        self.0.read().base.as_constr()
+    }
+
+    fn set_constr(self, mc: MutationContext<'gc, '_>, constr: Object<'gc>) {
+        self.0.write(mc).base.set_constr(constr);
+    }
+
     fn as_display_object(&self) -> Option<DisplayObject<'gc>> {
         self.0.read().display_object
     }
@@ -300,11 +284,7 @@ impl<'gc> TObject<'gc> for StageObject<'gc> {
         Err("Not a callable function!".into())
     }
 
-    fn construct(
-        &self,
-        activation: &mut Activation<'_, 'gc, '_>,
-        _args: &[Value<'gc>],
-    ) -> Result<Object<'gc>, Error> {
+    fn derive(&self, activation: &mut Activation<'_, 'gc, '_>) -> Result<Object<'gc>, Error> {
         let this: Object<'gc> = Object::StageObject(*self);
         let base = ScriptObjectData::base_new(Some(this), ScriptObjectClass::NoClass);
 
@@ -318,28 +298,6 @@ impl<'gc> TObject<'gc> for StageObject<'gc> {
         .into())
     }
 
-    fn derive(
-        &self,
-        activation: &mut Activation<'_, 'gc, '_>,
-        class: GcCell<'gc, Class<'gc>>,
-        scope: Option<GcCell<'gc, Scope<'gc>>>,
-    ) -> Result<Object<'gc>, Error> {
-        let this: Object<'gc> = Object::StageObject(*self);
-        let base = ScriptObjectData::base_new(
-            Some(this),
-            ScriptObjectClass::InstancePrototype(class, scope),
-        );
-
-        Ok(StageObject(GcCell::allocate(
-            activation.context.gc_context,
-            StageObjectData {
-                base,
-                display_object: None,
-            },
-        ))
-        .into())
-    }
-
     fn value_of(&self, _mc: MutationContext<'gc, '_>) -> Result<Value<'gc>, Error> {
         Ok(Value::Object(Object::from(*self)))
     }
diff --git a/core/src/avm2/object/xml_object.rs b/core/src/avm2/object/xml_object.rs
index 2021061f4..7a809facf 100644
--- a/core/src/avm2/object/xml_object.rs
+++ b/core/src/avm2/object/xml_object.rs
@@ -15,20 +15,11 @@ use gc_arena::{Collect, GcCell, MutationContext};
 
 /// A class instance deriver that constructs XML objects.
 pub fn xml_deriver<'gc>(
-    mut constr: Object<'gc>,
+    constr: Object<'gc>,
+    proto: Object<'gc>,
     activation: &mut Activation<'_, 'gc, '_>,
-    class: GcCell<'gc, Class<'gc>>,
-    scope: Option<GcCell<'gc, Scope<'gc>>>,
 ) -> Result<Object<'gc>, Error> {
-    let base_proto = constr
-        .get_property(
-            constr,
-            &QName::new(Namespace::public(), "prototype"),
-            activation,
-        )?
-        .coerce_to_object(activation)?;
-
-    XmlObject::derive(base_proto, activation.context.gc_context, class, scope)
+    XmlObject::derive(constr, proto, activation.context.gc_context)
 }
 
 #[derive(Clone, Collect, Debug, Copy)]
@@ -45,15 +36,12 @@ pub struct XmlObjectData<'gc> {
 impl<'gc> XmlObject<'gc> {
     /// Instantiate an xml subclass.
     pub fn derive(
+        constr: Object<'gc>,
         base_proto: Object<'gc>,
         mc: MutationContext<'gc, '_>,
-        class: GcCell<'gc, Class<'gc>>,
-        scope: Option<GcCell<'gc, Scope<'gc>>>,
     ) -> Result<Object<'gc>, Error> {
-        let base = ScriptObjectData::base_new(
-            Some(base_proto),
-            ScriptObjectClass::InstancePrototype(class, scope),
-        );
+        let base =
+            ScriptObjectData::base_new(Some(base_proto), ScriptObjectClass::ClassInstance(constr));
 
         Ok(XmlObject(GcCell::allocate(mc, XmlObjectData { base })).into())
     }
@@ -72,26 +60,15 @@ impl<'gc> TObject<'gc> for XmlObject<'gc> {
     impl_avm2_custom_object!(base);
     impl_avm2_custom_object_properties!(base);
 
-    fn construct(
-        &self,
-        activation: &mut Activation<'_, 'gc, '_>,
-        _args: &[Value<'gc>],
-    ) -> Result<Object<'gc>, Error> {
+    fn derive(&self, activation: &mut Activation<'_, 'gc, '_>) -> Result<Object<'gc>, Error> {
         let this: Object<'gc> = Object::XmlObject(*self);
-        Ok(Self::empty_object(
-            activation.context.gc_context,
-            Some(this),
-        ))
-    }
+        let base = ScriptObjectData::base_new(Some(this), ScriptObjectClass::NoClass);
 
-    fn derive(
-        &self,
-        activation: &mut Activation<'_, 'gc, '_>,
-        class: GcCell<'gc, Class<'gc>>,
-        scope: Option<GcCell<'gc, Scope<'gc>>>,
-    ) -> Result<Object<'gc>, Error> {
-        let this: Object<'gc> = Object::XmlObject(*self);
-        Self::derive(this, activation.context.gc_context, class, scope)
+        Ok(XmlObject(GcCell::allocate(
+            activation.context.gc_context,
+            XmlObjectData { base },
+        ))
+        .into())
     }
 
     fn value_of(&self, _mc: MutationContext<'gc, '_>) -> Result<Value<'gc>, Error> {
diff --git a/core/src/avm2/property.rs b/core/src/avm2/property.rs
index 3321aab54..7c59210b2 100644
--- a/core/src/avm2/property.rs
+++ b/core/src/avm2/property.rs
@@ -131,14 +131,14 @@ impl<'gc> Property<'gc> {
     pub fn get(
         &self,
         this: Object<'gc>,
-        base_proto: Option<Object<'gc>>,
+        base_constr: Option<Object<'gc>>,
     ) -> Result<ReturnValue<'gc>, Error> {
         match self {
             Property::Virtual { get: Some(get), .. } => Ok(ReturnValue::defer_execution(
                 *get,
                 Some(this),
                 vec![],
-                base_proto,
+                base_constr,
             )),
             Property::Virtual { get: None, .. } => Ok(Value::Undefined.into()),
             Property::Stored { value, .. } => Ok(value.to_owned().into()),
@@ -159,7 +159,7 @@ impl<'gc> Property<'gc> {
     pub fn set(
         &mut self,
         this: Object<'gc>,
-        base_proto: Option<Object<'gc>>,
+        base_constr: Option<Object<'gc>>,
         new_value: impl Into<Value<'gc>>,
     ) -> Result<ReturnValue<'gc>, Error> {
         match self {
@@ -169,7 +169,7 @@ impl<'gc> Property<'gc> {
                         *function,
                         Some(this),
                         vec![new_value.into()],
-                        base_proto,
+                        base_constr,
                     ));
                 }
 
@@ -203,7 +203,7 @@ impl<'gc> Property<'gc> {
     pub fn init(
         &mut self,
         this: Object<'gc>,
-        base_proto: Option<Object<'gc>>,
+        base_constr: Option<Object<'gc>>,
         new_value: impl Into<Value<'gc>>,
     ) -> Result<ReturnValue<'gc>, Error> {
         match self {
@@ -213,7 +213,7 @@ impl<'gc> Property<'gc> {
                         *function,
                         Some(this),
                         vec![new_value.into()],
-                        base_proto,
+                        base_constr,
                     ));
                 }
 
diff --git a/core/src/avm2/return_value.rs b/core/src/avm2/return_value.rs
index f1a0a154f..c8b587b9a 100644
--- a/core/src/avm2/return_value.rs
+++ b/core/src/avm2/return_value.rs
@@ -37,7 +37,7 @@ pub enum ReturnValue<'gc> {
         callee: Object<'gc>,
         unbound_reciever: Option<Object<'gc>>,
         arguments: Vec<Value<'gc>>,
-        base_proto: Option<Object<'gc>>,
+        base_constr: Option<Object<'gc>>,
     },
 }
 
@@ -49,13 +49,13 @@ impl fmt::Debug for ReturnValue<'_> {
                 callee,
                 unbound_reciever,
                 arguments,
-                base_proto,
+                base_constr,
             } => f
                 .debug_struct("ReturnValue")
                 .field("callee", callee)
                 .field("unbound_reciever", unbound_reciever)
                 .field("arguments", arguments)
-                .field("base_proto", base_proto)
+                .field("base_constr", base_constr)
                 .finish(),
         }
     }
@@ -67,13 +67,13 @@ impl<'gc> ReturnValue<'gc> {
         callee: Object<'gc>,
         unbound_reciever: Option<Object<'gc>>,
         arguments: Vec<Value<'gc>>,
-        base_proto: Option<Object<'gc>>,
+        base_constr: Option<Object<'gc>>,
     ) -> Self {
         Self::ResultOf {
             callee,
             unbound_reciever,
             arguments,
-            base_proto,
+            base_constr,
         }
     }
 
@@ -88,12 +88,12 @@ impl<'gc> ReturnValue<'gc> {
                 callee,
                 unbound_reciever,
                 arguments,
-                base_proto,
+                base_constr,
             } => callee.as_executable().unwrap().exec(
                 unbound_reciever,
                 &arguments,
                 activation,
-                base_proto,
+                base_constr,
                 callee,
             ),
         }
diff --git a/core/src/avm2/script.rs b/core/src/avm2/script.rs
index d39a809ed..0d96caaf5 100644
--- a/core/src/avm2/script.rs
+++ b/core/src/avm2/script.rs
@@ -4,6 +4,7 @@ use crate::avm2::activation::Activation;
 use crate::avm2::class::Class;
 use crate::avm2::domain::Domain;
 use crate::avm2::method::{BytecodeMethod, Method};
+use crate::avm2::names::{Namespace, QName};
 use crate::avm2::object::{DomainObject, Object, TObject};
 use crate::avm2::scope::Scope;
 use crate::avm2::string::AvmString;
@@ -109,8 +110,7 @@ impl<'gc> TranslationUnit<'gc> {
     pub fn load_class(
         self,
         class_index: u32,
-        avm2: &mut Avm2<'gc>,
-        mc: MutationContext<'gc, '_>,
+        uc: &mut UpdateContext<'_, 'gc, '_>,
     ) -> Result<GcCell<'gc, Class<'gc>>, Error> {
         let read = self.0.read();
         if let Some(class) = read.classes.get(&class_index) {
@@ -119,10 +119,15 @@ impl<'gc> TranslationUnit<'gc> {
 
         drop(read);
 
-        let class = Class::from_abc_index(self, class_index, mc)?;
-        self.0.write(mc).classes.insert(class_index, class);
+        let class = Class::from_abc_index(self, class_index, uc.gc_context)?;
+        self.0
+            .write(uc.gc_context)
+            .classes
+            .insert(class_index, class);
 
-        class.write(mc).load_traits(self, class_index, avm2, mc)?;
+        class
+            .write(uc.gc_context)
+            .load_traits(self, class_index, uc)?;
 
         Ok(class)
     }
@@ -131,8 +136,7 @@ impl<'gc> TranslationUnit<'gc> {
     pub fn load_script(
         self,
         script_index: u32,
-        avm2: &mut Avm2<'gc>,
-        mc: MutationContext<'gc, '_>,
+        uc: &mut UpdateContext<'_, 'gc, '_>,
     ) -> Result<Script<'gc>, Error> {
         let read = self.0.read();
         if let Some(scripts) = read.scripts.get(&script_index) {
@@ -143,15 +147,32 @@ impl<'gc> TranslationUnit<'gc> {
 
         drop(read);
 
-        let global = DomainObject::from_domain(mc, Some(avm2.prototypes().global), domain);
+        let mut activation = Activation::from_nothing(uc.reborrow());
 
-        let mut script = Script::from_abc_index(self, script_index, global, mc)?;
-        self.0.write(mc).scripts.insert(script_index, script);
+        let mut global_proto = activation.context.avm2.prototypes().global;
+        let global_constr = global_proto
+            .get_property(
+                global_proto,
+                &QName::new(Namespace::public(), "constructor"),
+                &mut activation,
+            )?
+            .coerce_to_object(&mut activation)?;
 
-        script.load_traits(self, script_index, avm2, mc)?;
+        drop(activation);
+
+        let global =
+            DomainObject::from_domain(uc.gc_context, global_constr, Some(global_proto), domain);
+
+        let mut script = Script::from_abc_index(self, script_index, global, uc.gc_context)?;
+        self.0
+            .write(uc.gc_context)
+            .scripts
+            .insert(script_index, script);
+
+        script.load_traits(self, script_index, uc)?;
 
         for traitdef in script.traits()?.iter() {
-            domain.export_definition(traitdef.name().clone(), script, mc)?;
+            domain.export_definition(traitdef.name().clone(), script, uc.gc_context)?;
         }
 
         Ok(script)
@@ -302,10 +323,9 @@ impl<'gc> Script<'gc> {
         &mut self,
         unit: TranslationUnit<'gc>,
         script_index: u32,
-        avm2: &mut Avm2<'gc>,
-        mc: MutationContext<'gc, '_>,
+        uc: &mut UpdateContext<'_, 'gc, '_>,
     ) -> Result<(), Error> {
-        let mut write = self.0.write(mc);
+        let mut write = self.0.write(uc.gc_context);
 
         if write.traits_loaded {
             return Ok(());
@@ -323,9 +343,9 @@ impl<'gc> Script<'gc> {
         for abc_trait in script.traits.iter() {
             drop(write);
 
-            let newtrait = Trait::from_abc_trait(unit, abc_trait, avm2, mc)?;
+            let newtrait = Trait::from_abc_trait(unit, abc_trait, uc)?;
 
-            write = self.0.write(mc);
+            write = self.0.write(uc.gc_context);
             write.traits.push(newtrait);
         }
 
diff --git a/core/src/avm2/traits.rs b/core/src/avm2/traits.rs
index 81d43c750..6b5f3f33d 100644
--- a/core/src/avm2/traits.rs
+++ b/core/src/avm2/traits.rs
@@ -5,9 +5,10 @@ use crate::avm2::method::Method;
 use crate::avm2::names::{Multiname, QName};
 use crate::avm2::script::TranslationUnit;
 use crate::avm2::value::{abc_default_value, Value};
-use crate::avm2::{Avm2, Error};
+use crate::avm2::Error;
+use crate::context::UpdateContext;
 use bitflags::bitflags;
-use gc_arena::{Collect, GcCell, MutationContext};
+use gc_arena::{Collect, GcCell};
 use swf::avm2::types::{Trait as AbcTrait, TraitKind as AbcTraitKind};
 
 bitflags! {
@@ -179,10 +180,9 @@ impl<'gc> Trait<'gc> {
     pub fn from_abc_trait(
         unit: TranslationUnit<'gc>,
         abc_trait: &AbcTrait,
-        avm2: &mut Avm2<'gc>,
-        mc: MutationContext<'gc, '_>,
+        uc: &mut UpdateContext<'_, 'gc, '_>,
     ) -> Result<Self, Error> {
-        let name = QName::from_abc_multiname(unit, abc_trait.name.clone(), mc)?;
+        let name = QName::from_abc_multiname(unit, abc_trait.name.clone(), uc.gc_context)?;
 
         Ok(match &abc_trait.kind {
             AbcTraitKind::Slot {
@@ -197,10 +197,14 @@ impl<'gc> Trait<'gc> {
                     type_name: if type_name.0 == 0 {
                         Multiname::any()
                     } else {
-                        Multiname::from_abc_multiname_static(unit, type_name.clone(), mc)?
+                        Multiname::from_abc_multiname_static(
+                            unit,
+                            type_name.clone(),
+                            uc.gc_context,
+                        )?
                     },
                     default_value: if let Some(dv) = value {
-                        Some(abc_default_value(unit, dv, avm2, mc)?)
+                        Some(abc_default_value(unit, dv, uc)?)
                     } else {
                         None
                     },
@@ -211,7 +215,7 @@ impl<'gc> Trait<'gc> {
                 attributes: trait_attribs_from_abc_traits(abc_trait),
                 kind: TraitKind::Method {
                     disp_id: *disp_id,
-                    method: unit.load_method(method.0, mc)?,
+                    method: unit.load_method(method.0, uc.gc_context)?,
                 },
             },
             AbcTraitKind::Getter { disp_id, method } => Trait {
@@ -219,7 +223,7 @@ impl<'gc> Trait<'gc> {
                 attributes: trait_attribs_from_abc_traits(abc_trait),
                 kind: TraitKind::Getter {
                     disp_id: *disp_id,
-                    method: unit.load_method(method.0, mc)?,
+                    method: unit.load_method(method.0, uc.gc_context)?,
                 },
             },
             AbcTraitKind::Setter { disp_id, method } => Trait {
@@ -227,7 +231,7 @@ impl<'gc> Trait<'gc> {
                 attributes: trait_attribs_from_abc_traits(abc_trait),
                 kind: TraitKind::Setter {
                     disp_id: *disp_id,
-                    method: unit.load_method(method.0, mc)?,
+                    method: unit.load_method(method.0, uc.gc_context)?,
                 },
             },
             AbcTraitKind::Class { slot_id, class } => Trait {
@@ -235,7 +239,7 @@ impl<'gc> Trait<'gc> {
                 attributes: trait_attribs_from_abc_traits(abc_trait),
                 kind: TraitKind::Class {
                     slot_id: *slot_id,
-                    class: unit.load_class(class.0, avm2, mc)?,
+                    class: unit.load_class(class.0, uc)?,
                 },
             },
             AbcTraitKind::Function { slot_id, function } => Trait {
@@ -243,7 +247,7 @@ impl<'gc> Trait<'gc> {
                 attributes: trait_attribs_from_abc_traits(abc_trait),
                 kind: TraitKind::Function {
                     slot_id: *slot_id,
-                    function: unit.load_method(function.0, mc)?,
+                    function: unit.load_method(function.0, uc.gc_context)?,
                 },
             },
             AbcTraitKind::Const {
@@ -258,10 +262,14 @@ impl<'gc> Trait<'gc> {
                     type_name: if type_name.0 == 0 {
                         Multiname::any()
                     } else {
-                        Multiname::from_abc_multiname_static(unit, type_name.clone(), mc)?
+                        Multiname::from_abc_multiname_static(
+                            unit,
+                            type_name.clone(),
+                            uc.gc_context,
+                        )?
                     },
                     default_value: if let Some(dv) = value {
-                        Some(abc_default_value(unit, dv, avm2, mc)?)
+                        Some(abc_default_value(unit, dv, uc)?)
                     } else {
                         None
                     },
diff --git a/core/src/avm2/value.rs b/core/src/avm2/value.rs
index bf7999fb5..478186fc6 100644
--- a/core/src/avm2/value.rs
+++ b/core/src/avm2/value.rs
@@ -6,7 +6,8 @@ use crate::avm2::names::QName;
 use crate::avm2::object::{NamespaceObject, Object, PrimitiveObject, TObject};
 use crate::avm2::script::TranslationUnit;
 use crate::avm2::string::AvmString;
-use crate::avm2::{Avm2, Error};
+use crate::avm2::Error;
+use crate::context::UpdateContext;
 use crate::ecma_conversions::{f64_to_wrapping_i32, f64_to_wrapping_u32};
 use gc_arena::{Collect, MutationContext};
 use std::cell::Ref;
@@ -184,14 +185,15 @@ pub fn abc_double(translation_unit: TranslationUnit<'_>, index: Index<f64>) -> R
 pub fn abc_default_value<'gc>(
     translation_unit: TranslationUnit<'gc>,
     default: &AbcDefaultValue,
-    avm2: &mut Avm2<'gc>,
-    mc: MutationContext<'gc, '_>,
+    uc: &mut UpdateContext<'_, 'gc, '_>,
 ) -> Result<Value<'gc>, Error> {
     match default {
         AbcDefaultValue::Int(i) => abc_int(translation_unit, *i).map(|v| v.into()),
         AbcDefaultValue::Uint(u) => abc_uint(translation_unit, *u).map(|v| v.into()),
         AbcDefaultValue::Double(d) => abc_double(translation_unit, *d).map(|v| v.into()),
-        AbcDefaultValue::String(s) => translation_unit.pool_string(s.0, mc).map(|v| v.into()),
+        AbcDefaultValue::String(s) => translation_unit
+            .pool_string(s.0, uc.gc_context)
+            .map(|v| v.into()),
         AbcDefaultValue::True => Ok(true.into()),
         AbcDefaultValue::False => Ok(false.into()),
         AbcDefaultValue::Null => Ok(Value::Null),
@@ -202,12 +204,28 @@ pub fn abc_default_value<'gc>(
         | AbcDefaultValue::Protected(ns)
         | AbcDefaultValue::Explicit(ns)
         | AbcDefaultValue::StaticProtected(ns)
-        | AbcDefaultValue::Private(ns) => Ok(NamespaceObject::from_namespace(
-            Namespace::from_abc_namespace(translation_unit, ns.clone(), mc)?,
-            avm2.prototypes().namespace,
-            mc,
-        )?
-        .into()),
+        | AbcDefaultValue::Private(ns) => {
+            let mut activation = Activation::from_nothing(uc.reborrow());
+
+            let mut ns_proto = activation.avm2().prototypes().namespace;
+            let ns_constr = ns_proto
+                .get_property(
+                    ns_proto,
+                    &QName::new(Namespace::public(), "constructor"),
+                    &mut activation,
+                )?
+                .coerce_to_object(&mut activation)?;
+
+            drop(activation);
+
+            Ok(NamespaceObject::from_namespace(
+                Namespace::from_abc_namespace(translation_unit, ns.clone(), uc.gc_context)?,
+                ns_constr,
+                ns_proto,
+                uc.gc_context,
+            )?
+            .into())
+        }
     }
 }
 
@@ -561,7 +579,7 @@ impl<'gc> Value<'gc> {
             _ => {}
         };
 
-        let proto = match self {
+        let mut proto = match self {
             Value::Bool(_) => activation.avm2().prototypes().boolean,
             Value::Number(_) => activation.avm2().prototypes().number,
             Value::Unsigned(_) => activation.avm2().prototypes().uint,
@@ -569,8 +587,15 @@ impl<'gc> Value<'gc> {
             Value::String(_) => activation.avm2().prototypes().string,
             _ => unreachable!(),
         };
+        let constr = proto
+            .get_property(
+                proto,
+                &QName::new(Namespace::public(), "constructor"),
+                activation,
+            )?
+            .coerce_to_object(activation)?;
 
-        PrimitiveObject::from_primitive(self.clone(), proto, activation.context.gc_context)
+        PrimitiveObject::from_primitive(self.clone(), constr, proto, activation.context.gc_context)
     }
 
     /// Determine if two values are abstractly equal to each other.
diff --git a/core/src/display_object/avm2_button.rs b/core/src/display_object/avm2_button.rs
index 4827779dd..467f6dd09 100644
--- a/core/src/display_object/avm2_button.rs
+++ b/core/src/display_object/avm2_button.rs
@@ -441,10 +441,22 @@ impl<'gc> TDisplayObject<'gc> for Avm2Button<'gc> {
         }
 
         if self.0.read().object.is_none() {
+            let mut activation = Avm2Activation::from_nothing(context.reborrow());
+            let mut simplebutton_proto = activation.avm2().prototypes().simplebutton;
+            let simplebutton_constr = simplebutton_proto
+                .get_property(
+                    simplebutton_proto,
+                    &Avm2QName::new(Avm2Namespace::public(), "constructor"),
+                    &mut activation,
+                )
+                .unwrap()
+                .coerce_to_object(&mut activation)
+                .unwrap();
             let object = Avm2StageObject::for_display_object(
                 context.gc_context,
                 (*self).into(),
-                context.avm2.prototypes().simplebutton,
+                simplebutton_constr,
+                simplebutton_proto,
             );
             self.0.write(context.gc_context).object = Some(object.into());
 
diff --git a/core/src/display_object/edit_text.rs b/core/src/display_object/edit_text.rs
index 844da9517..7cfba74aa 100644
--- a/core/src/display_object/edit_text.rs
+++ b/core/src/display_object/edit_text.rs
@@ -1509,22 +1509,28 @@ impl<'gc> EditText<'gc> {
         context: &mut UpdateContext<'_, 'gc, '_>,
         display_object: DisplayObject<'gc>,
     ) {
-        let mut proto = context.avm2.prototypes().textfield;
-        let object: Avm2Object<'gc> =
-            Avm2StageObject::for_display_object(context.gc_context, display_object, proto).into();
-
+        let mut textfield_proto = context.avm2.prototypes().textfield;
         let mut activation = Avm2Activation::from_nothing(context.reborrow());
-        let constr = proto
+        let textfield_constr = textfield_proto
             .get_property(
-                proto,
+                textfield_proto,
                 &Avm2QName::new(Avm2Namespace::public(), "constructor"),
                 &mut activation,
             )
-            .unwrap()
-            .coerce_to_object(&mut activation)
-            .unwrap();
+            .and_then(|v| v.coerce_to_object(&mut activation))
+            .expect("Textfield proto needs constr");
 
-        if let Err(e) = constr.call(Some(object), &[], &mut activation, Some(proto)) {
+        let object: Avm2Object<'gc> = Avm2StageObject::for_display_object(
+            activation.context.gc_context,
+            display_object,
+            textfield_constr,
+            textfield_proto,
+        )
+        .into();
+
+        if let Err(e) =
+            textfield_constr.call(Some(object), &[], &mut activation, Some(textfield_constr))
+        {
             log::error!(
                 "Got {} when constructing AVM2 side of dynamic text field",
                 e
diff --git a/core/src/display_object/graphic.rs b/core/src/display_object/graphic.rs
index 4da64a513..ba16ef449 100644
--- a/core/src/display_object/graphic.rs
+++ b/core/src/display_object/graphic.rs
@@ -118,10 +118,10 @@ impl<'gc> TDisplayObject<'gc> for Graphic<'gc> {
         if self.avm_type() == AvmType::Avm2 && matches!(self.object2(), Avm2Value::Undefined) {
             let mut allocator = || {
                 let mut activation = Avm2Activation::from_nothing(context.reborrow());
-                let mut proto = activation.context.avm2.prototypes().shape;
-                let constr = proto
+                let mut shape_proto = activation.context.avm2.prototypes().shape;
+                let shape_constr = shape_proto
                     .get_property(
-                        proto,
+                        shape_proto,
                         &Avm2QName::new(Avm2Namespace::public(), "constructor"),
                         &mut activation,
                     )?
@@ -130,10 +130,11 @@ impl<'gc> TDisplayObject<'gc> for Graphic<'gc> {
                 let object = Avm2StageObject::for_display_object(
                     activation.context.gc_context,
                     (*self).into(),
-                    proto,
+                    shape_constr,
+                    shape_proto,
                 )
                 .into();
-                constr.call(Some(object), &[], &mut activation, Some(proto))?;
+                shape_constr.call(Some(object), &[], &mut activation, Some(shape_proto))?;
 
                 Ok(object)
             };
diff --git a/core/src/display_object/movie_clip.rs b/core/src/display_object/movie_clip.rs
index 449585034..3f9043844 100644
--- a/core/src/display_object/movie_clip.rs
+++ b/core/src/display_object/movie_clip.rs
@@ -1529,7 +1529,7 @@ impl<'gc> MovieClip<'gc> {
 
         let mut constr_thing = || {
             let mut activation = Avm2Activation::from_nothing(context.reborrow());
-            let proto = constructor
+            let mc_proto = constructor
                 .get_property(
                     constructor,
                     &Avm2QName::new(Avm2Namespace::public(), "prototype"),
@@ -1539,7 +1539,8 @@ impl<'gc> MovieClip<'gc> {
             let object = Avm2StageObject::for_display_object(
                 activation.context.gc_context,
                 display_object,
-                proto,
+                constructor,
+                mc_proto,
             )
             .into();
 
@@ -1560,7 +1561,7 @@ impl<'gc> MovieClip<'gc> {
     /// will allocate the object first before doing so. This function is
     /// intended to be called from `post_instantiate`.
     fn construct_as_avm2_object(self, context: &mut UpdateContext<'_, 'gc, '_>) {
-        let mut constructor = self.0.read().avm2_constructor.unwrap_or_else(|| {
+        let constructor = self.0.read().avm2_constructor.unwrap_or_else(|| {
             let mut activation = Avm2Activation::from_nothing(context.reborrow());
             let mut mc_proto = activation.context.avm2.prototypes().movieclip;
             mc_proto
@@ -1577,14 +1578,7 @@ impl<'gc> MovieClip<'gc> {
         if let Avm2Value::Object(object) = self.object2() {
             let mut constr_thing = || {
                 let mut activation = Avm2Activation::from_nothing(context.reborrow());
-                let proto = constructor
-                    .get_property(
-                        constructor,
-                        &Avm2QName::new(Avm2Namespace::public(), "prototype"),
-                        &mut activation,
-                    )?
-                    .coerce_to_object(&mut activation)?;
-                constructor.call(Some(object), &[], &mut activation, Some(proto))?;
+                constructor.call(Some(object), &[], &mut activation, Some(constructor))?;
 
                 Ok(())
             };
diff --git a/core/src/display_object/stage.rs b/core/src/display_object/stage.rs
index 40900e31d..dc5aa9b83 100644
--- a/core/src/display_object/stage.rs
+++ b/core/src/display_object/stage.rs
@@ -4,7 +4,7 @@ use crate::avm1::Object as Avm1Object;
 use crate::avm2::{
     Activation as Avm2Activation, Event as Avm2Event, Namespace as Avm2Namespace,
     Object as Avm2Object, QName as Avm2QName, ScriptObject as Avm2ScriptObject,
-    StageObject as Avm2StageObject, Value as Avm2Value,
+    StageObject as Avm2StageObject, TObject as Avm2TObject, Value as Avm2Value,
 };
 use crate::backend::ui::UiBackend;
 use crate::config::Letterbox;
@@ -518,28 +518,32 @@ impl<'gc> TDisplayObject<'gc> for Stage<'gc> {
         _instantiated_by: Instantiator,
         _run_frame: bool,
     ) {
-        let stage_proto = context.avm2.prototypes().stage;
-        let avm2_stage =
-            Avm2StageObject::for_display_object(context.gc_context, (*self).into(), stage_proto);
-
-        // TODO: Replace this when we have a convenience method for constructing AVM2 native objects.
-        // TODO: We should only do this if the movie is actually an AVM2 movie.
-        // This is necessary for EventDispatcher super-constructor to run.
-        use crate::avm2::TObject;
+        let mut stage_proto = context.avm2.prototypes().stage;
         let mut activation = Avm2Activation::from_nothing(context.reborrow());
-        let mut proto = activation.context.avm2.prototypes().stage;
-        if let Err(e) = proto
+        let stage_constr = stage_proto
             .get_property(
-                proto,
+                stage_proto,
                 &Avm2QName::new(Avm2Namespace::public(), "constructor"),
                 &mut activation,
             )
             .and_then(|v| v.coerce_to_object(&mut activation))
-            .and_then(|constr| {
-                // TODO: Stage's AS-visible constructor actually throws. Have to call non-throwing native constructor here.
-                constr.call(Some(avm2_stage.into()), &[], &mut activation, Some(proto))
-            })
-        {
+            .expect("Stage proto needs constr");
+        let avm2_stage = Avm2StageObject::for_display_object(
+            activation.context.gc_context,
+            (*self).into(),
+            stage_constr,
+            stage_proto,
+        );
+
+        // TODO: Replace this when we have a convenience method for constructing AVM2 native objects.
+        // TODO: We should only do this if the movie is actually an AVM2 movie.
+        // This is necessary for EventDispatcher super-constructor to run.
+        if let Err(e) = stage_constr.call(
+            Some(avm2_stage.into()),
+            &[],
+            &mut activation,
+            Some(stage_constr),
+        ) {
             log::error!("Unable to construct AVM2 Stage: {}", e);
         }
 
diff --git a/core/src/display_object/video.rs b/core/src/display_object/video.rs
index eb7a8fa2c..b57269a01 100644
--- a/core/src/display_object/video.rs
+++ b/core/src/display_object/video.rs
@@ -1,7 +1,10 @@
 //! Video player display object
 
 use crate::avm1::{Object as Avm1Object, StageObject as Avm1StageObject};
-use crate::avm2::{Object as Avm2Object, StageObject as Avm2StageObject};
+use crate::avm2::{
+    Activation as Avm2Activation, Namespace as Avm2Namespace, Object as Avm2Object,
+    QName as Avm2QName, StageObject as Avm2StageObject, TObject as Avm2TObject,
+};
 use crate::backend::render::BitmapInfo;
 use crate::backend::video::{EncodedFrame, VideoStreamHandle};
 use crate::bounding_box::BoundingBox;
@@ -381,13 +384,25 @@ impl<'gc> TDisplayObject<'gc> for Video<'gc> {
     fn construct_frame(&self, context: &mut UpdateContext<'_, 'gc, '_>) {
         let vm_type = self.avm_type();
         if vm_type == AvmType::Avm2 && matches!(self.object2(), Avm2Value::Undefined) {
+            let mut video_proto = context.avm2.prototypes().video;
+            let mut activation = Avm2Activation::from_nothing(context.reborrow());
+            let video_constr = video_proto
+                .get_property(
+                    video_proto,
+                    &Avm2QName::new(Avm2Namespace::public(), "constructor"),
+                    &mut activation,
+                )
+                .and_then(|v| v.coerce_to_object(&mut activation))
+                .expect("Video proto needs constr");
+
             let object: Avm2Object<'_> = Avm2StageObject::for_display_object(
-                context.gc_context,
+                activation.context.gc_context,
                 (*self).into(),
-                context.avm2.prototypes().video,
+                video_constr,
+                video_proto,
             )
             .into();
-            self.0.write(context.gc_context).object = Some(object.into());
+            self.0.write(activation.context.gc_context).object = Some(object.into());
         }
     }
 
diff --git a/core/src/html/text_format.rs b/core/src/html/text_format.rs
index ddfc4124c..94b2d219b 100644
--- a/core/src/html/text_format.rs
+++ b/core/src/html/text_format.rs
@@ -708,7 +708,7 @@ impl TextFormat {
             .coerce_to_object(activation)?;
         let mut object = Avm2ScriptObject::object(activation.context.gc_context, proto);
 
-        constr.call(Some(object), &[], activation, Some(proto))?;
+        constr.call(Some(object), &[], activation, Some(constr))?;
 
         object.set_property(
             object,
@@ -849,9 +849,20 @@ impl TextFormat {
 
         if let Some(ts) = &self.tab_stops {
             let tab_stop_storage = ts.iter().copied().collect();
+
+            let mut array_proto = activation.avm2().prototypes().array;
+            let array_constr = array_proto
+                .get_property(
+                    array_proto,
+                    &Avm2QName::new(Avm2Namespace::public(), "constructor"),
+                    activation,
+                )?
+                .coerce_to_object(activation)?;
+
             let tab_stops = Avm2ArrayObject::from_array(
                 tab_stop_storage,
-                activation.context.avm2.prototypes().array,
+                array_constr,
+                array_proto,
                 activation.context.gc_context,
             );
 
diff --git a/core/src/loader.rs b/core/src/loader.rs
index 6298732d8..f9d37afd4 100644
--- a/core/src/loader.rs
+++ b/core/src/loader.rs
@@ -2,7 +2,7 @@
 
 use crate::avm1::activation::{Activation, ActivationIdentifier};
 use crate::avm1::{Avm1, AvmString, Object, TObject, Value};
-use crate::avm2::Domain as Avm2Domain;
+use crate::avm2::{Activation as Avm2Activation, Domain as Avm2Domain};
 use crate::backend::navigator::OwnedFuture;
 use crate::context::{ActionQueue, ActionType};
 use crate::display_object::{DisplayObject, MorphShape, TDisplayObject};
@@ -498,11 +498,12 @@ impl<'gc> Loader<'gc> {
                             _ => unreachable!(),
                         };
 
-                        let domain =
-                            Avm2Domain::movie_domain(uc.gc_context, uc.avm2.global_domain());
-                        let library = uc.library.library_for_movie_mut(movie.clone());
-
-                        library.set_avm2_domain(domain);
+                        let mut activation = Avm2Activation::from_nothing(uc.reborrow());
+                        let parent_domain = activation.avm2().global_domain();
+                        let domain = Avm2Domain::movie_domain(&mut activation, parent_domain);
+                        uc.library
+                            .library_for_movie_mut(movie.clone())
+                            .set_avm2_domain(domain);
 
                         if let Some(broadcaster) = broadcaster {
                             Avm1::run_stack_frame_for_method(
diff --git a/core/src/player.rs b/core/src/player.rs
index 7a2d749db..7c68977d0 100644
--- a/core/src/player.rs
+++ b/core/src/player.rs
@@ -4,7 +4,7 @@ use crate::avm1::globals::system::SystemProperties;
 use crate::avm1::object::Object;
 use crate::avm1::property::Attribute;
 use crate::avm1::{Avm1, AvmString, ScriptObject, TObject, Timers, Value};
-use crate::avm2::{Avm2, Domain as Avm2Domain};
+use crate::avm2::{Activation as Avm2Activation, Avm2, Domain as Avm2Domain};
 use crate::backend::{
     audio::{AudioBackend, AudioManager},
     locale::LocaleBackend,
@@ -389,14 +389,21 @@ impl Player {
                 context.swf.width().to_pixels() as u32,
                 context.swf.height().to_pixels() as u32,
             );
-            let domain = Avm2Domain::movie_domain(context.gc_context, context.avm2.global_domain());
+
+            let mut activation = Avm2Activation::from_nothing(context.reborrow());
+            let global_domain = activation.avm2().global_domain();
+            let domain = Avm2Domain::movie_domain(&mut activation, global_domain);
+
+            drop(activation);
+
+            context
+                .library
+                .library_for_movie_mut(context.swf.clone())
+                .set_avm2_domain(domain);
+
             let root: DisplayObject =
                 MovieClip::from_movie(context.gc_context, context.swf.clone()).into();
 
-            let library = context.library.library_for_movie_mut(context.swf.clone());
-
-            library.set_avm2_domain(domain);
-
             root.set_depth(context.gc_context, 0);
             let flashvars = if !context.swf.parameters().is_empty() {
                 let object = ScriptObject::object(context.gc_context, None);