diff --git a/lib/hkStubs/CMakeLists.txt b/lib/hkStubs/CMakeLists.txt
index 19003e72..32952a7e 100644
--- a/lib/hkStubs/CMakeLists.txt
+++ b/lib/hkStubs/CMakeLists.txt
@@ -17,6 +17,7 @@ add_library(hkStubs OBJECT
   Havok/Common/Base/Memory/Allocator/hkMemoryAllocator.h
   Havok/Common/Base/Memory/Allocator/Lifo/hkLifoAllocator.h
   Havok/Common/Base/Memory/Router/hkMemoryRouter.h
+  Havok/Common/Base/Memory/Util/hkMemUtil.h
 
   Havok/Common/Base/Object/hkBaseObject.h
   Havok/Common/Base/Object/hkReferencedObject.cpp
@@ -73,6 +74,7 @@ add_library(hkStubs OBJECT
 
   Havok/Physics2012/Dynamics/Entity/hkpEntity.h
   Havok/Physics2012/Dynamics/Entity/hkpRigidBody.h
+  Havok/Physics2012/Dynamics/World/hkpPhysicsSystem.h
   Havok/Physics2012/Dynamics/World/hkpWorld.cpp
   Havok/Physics2012/Dynamics/World/hkpWorld.h
   Havok/Physics2012/Dynamics/World/hkpWorldCinfo.cpp
@@ -81,6 +83,8 @@ add_library(hkStubs OBJECT
   Havok/Physics2012/Dynamics/World/hkpWorldObject.h
   Havok/Physics2012/Dynamics/World/Memory/hkpWorldMemoryAvailableWatchDog.h
   Havok/Physics2012/Dynamics/World/Memory/Default/hkpDefaultWorldMemoryWatchDog.h
+
+  Havok/Physics2012/Utilities/Serialize/hkpPhysicsData.h
 )
 
 target_compile_options(hkStubs PRIVATE -fno-exceptions)
diff --git a/lib/hkStubs/Havok/Common/Base/Container/Array/hkArray.h b/lib/hkStubs/Havok/Common/Base/Container/Array/hkArray.h
index c80c5f74..1db2335e 100644
--- a/lib/hkStubs/Havok/Common/Base/Container/Array/hkArray.h
+++ b/lib/hkStubs/Havok/Common/Base/Container/Array/hkArray.h
@@ -2,6 +2,7 @@
 
 #include <Havok/Common/Base/Container/Array/hkArrayUtil.h>
 #include <Havok/Common/Base/Container/hkContainerAllocators.h>
+#include <Havok/Common/Base/Memory/Util/hkMemUtil.h>
 #include <Havok/Common/Base/Types/hkBaseDefs.h>
 #include <Havok/Common/Base/Types/hkBaseTypes.h>
 #include <type_traits>
@@ -188,6 +189,27 @@ inline void hkArrayBase<T>::_clearAndDeallocate(hkMemoryAllocator& allocator) {
     m_capacityAndFlags = DONT_DEALLOCATE_FLAG;
 }
 
+template <typename T>
+inline void hkArrayBase<T>::removeAt(int index) {
+    hkArrayUtil::destruct(&m_data[index], 1);
+    m_size--;
+    if (m_size != index)
+        hkMemUtil::memCpyOneAligned<sizeof(T), alignof(T)>(m_data + index, m_data + m_size);
+}
+
+template <typename T>
+inline void hkArrayBase<T>::removeAtAndCopy(int index) {
+    removeAtAndCopy(index, 1);
+}
+
+template <typename T>
+inline void hkArrayBase<T>::removeAtAndCopy(int index, int numToRemove) {
+    hkArrayUtil::destruct(m_data + index, numToRemove);
+    m_size -= numToRemove;
+    hkMemUtil::memCpy<alignof(T)>(m_data + index, m_data + index + numToRemove,
+                                  (m_size - index) * sizeof(T));
+}
+
 template <typename T>
 inline void hkArrayBase<T>::popBack(int numElemsToRemove) {
     hkArrayUtil::destruct(m_data + m_size - numElemsToRemove, numElemsToRemove);
diff --git a/lib/hkStubs/Havok/Common/Base/Container/String/hkStringPtr.h b/lib/hkStubs/Havok/Common/Base/Container/String/hkStringPtr.h
index b6a1eddd..35fabb72 100644
--- a/lib/hkStubs/Havok/Common/Base/Container/String/hkStringPtr.h
+++ b/lib/hkStubs/Havok/Common/Base/Container/String/hkStringPtr.h
@@ -11,6 +11,7 @@ public:
     };
 
     hkStringPtr();
+    explicit hkStringPtr(hkFinishLoadedObjectFlag f);
 
     inline const char* cString() const;
     inline operator const char*() const;
diff --git a/lib/hkStubs/Havok/Common/Base/Memory/Util/hkMemUtil.h b/lib/hkStubs/Havok/Common/Base/Memory/Util/hkMemUtil.h
new file mode 100644
index 00000000..e59d326b
--- /dev/null
+++ b/lib/hkStubs/Havok/Common/Base/Memory/Util/hkMemUtil.h
@@ -0,0 +1,61 @@
+#pragma once
+
+#include <Havok/Common/Base/hkBase.h>
+
+namespace hkMemUtil {
+
+template <unsigned int NBYTES>
+struct TypeFromAlign;
+
+template <>
+struct TypeFromAlign<1> {
+    using type = char;
+};
+
+template <>
+struct TypeFromAlign<2> {
+    using type = hkInt16;
+};
+
+template <>
+struct TypeFromAlign<4> {
+    using type = hkInt32;
+};
+
+template <>
+struct TypeFromAlign<8> {
+    using type = hkInt64;
+};
+
+template <unsigned int NBYTES>
+struct TypeFromAlign : public TypeFromAlign<NBYTES / 2> {};
+
+template <unsigned int ELEMENTSIZE, unsigned int ELEMENTALIGN>
+HK_FORCE_INLINE void memCpyOneAligned(void* dst, const void* src);
+
+template <unsigned int ELEMENTALIGN>
+HK_FORCE_INLINE void memCpy(void* dst, const void* src, int nbytes);
+
+void memCpy(void* dst, const void* src, int nbytes);
+void memCpyBackwards(void* dst, const void* src, int nbytes);
+void memMove(void* dst, const void* src, int nbytes);
+void memSet(void* dst, int c, int n);
+
+template <unsigned int ELEMENTSIZE, unsigned int ELEMENTALIGN>
+inline void memCpyOneAligned(void* dst, const void* src) {
+    using CopyType = typename TypeFromAlign<ELEMENTALIGN>::type;
+    unsigned int i = 0;
+    do {
+        static_cast<CopyType*>(dst)[i] = static_cast<const CopyType*>(src)[i];
+    } while (++i < ELEMENTSIZE / sizeof(CopyType));
+}
+
+template <unsigned int ELEMENTALIGN>
+inline void memCpy(void* dst, const void* src, int nbytes) {
+    using CopyType = typename TypeFromAlign<ELEMENTALIGN>::type;
+    for (int i = 0, j = 0; i < nbytes; i += sizeof(CopyType), ++j) {
+        static_cast<CopyType*>(dst)[j] = static_cast<const CopyType*>(src)[j];
+    }
+}
+
+}  // namespace hkMemUtil
diff --git a/lib/hkStubs/Havok/Physics2012/Dynamics/World/hkpPhysicsSystem.h b/lib/hkStubs/Havok/Physics2012/Dynamics/World/hkpPhysicsSystem.h
new file mode 100644
index 00000000..51c04d31
--- /dev/null
+++ b/lib/hkStubs/Havok/Physics2012/Dynamics/World/hkpPhysicsSystem.h
@@ -0,0 +1,115 @@
+#pragma once
+
+#include <Havok/Common/Base/hkBase.h>
+
+class hkTransform;
+class hkpRigidBody;
+class hkpConstraintInstance;
+class hkpAction;
+class hkpPhantom;
+
+class hkpPhysicsSystem : public hkReferencedObject {
+public:
+    HK_DECLARE_CLASS_ALLOCATOR(hkpPhysicsSystem)
+    HK_DECLARE_REFLECTION()
+
+    hkpPhysicsSystem();
+
+    explicit hkpPhysicsSystem(hkFinishLoadedObjectFlag f)
+        : hkReferencedObject(f), m_rigidBodies(f), m_constraints(f), m_actions(f), m_phantoms(f),
+          m_name(f) {}
+
+    ~hkpPhysicsSystem() override;
+
+    enum CloneConstraintMode {
+        CLONE_SHALLOW_IF_NOT_CONSTRAINED_TO_WORLD = 0,
+        CLONE_DEEP_WITH_MOTORS = 1,
+        CLONE_FORCE_SHALLOW = 2,
+        CLONE_DEFAULT = 0,
+    };
+
+    virtual hkpPhysicsSystem* clone(CloneConstraintMode cloneMode = CLONE_DEFAULT) const;
+
+    void removeAll();
+
+    void copy(const hkpPhysicsSystem& toCopy);
+
+    void addRigidBody(hkpRigidBody* rb);
+    void addPhantom(hkpPhantom* p);
+    void addConstraint(hkpConstraintInstance* c);
+    void addAction(hkpAction* a);
+
+    void removeRigidBody(int i);
+    void removePhantom(int i);
+    void removeConstraint(int i);
+    void removeAction(int i);
+
+    void removeNullPhantoms();
+
+    inline const hkArray<hkpRigidBody*>& getRigidBodies() const;
+    inline const hkArray<hkpPhantom*>& getPhantoms() const;
+    inline const hkArray<hkpConstraintInstance*>& getConstraints() const;
+    inline const hkArray<hkpAction*>& getActions() const;
+
+    inline const char* getName() const;
+    inline void setName(const char* name);
+
+    inline hkUlong getUserData() const;
+    inline void setUserData(hkUlong d);
+
+    inline hkBool isActive() const;
+    inline void setActive(hkBool active);
+
+    virtual hkBool hasContacts() { return false; }
+
+    void transform(const hkTransform& transformation);
+
+protected:
+    hkArray<hkpRigidBody*> m_rigidBodies;
+    hkArray<hkpConstraintInstance*> m_constraints;
+    hkArray<hkpAction*> m_actions;
+    hkArray<hkpPhantom*> m_phantoms;
+    hkStringPtr m_name;
+    hkUlong m_userData;
+    hkBool m_active;
+};
+
+inline const hkArray<hkpRigidBody*>& hkpPhysicsSystem::getRigidBodies() const {
+    return m_rigidBodies;
+}
+
+inline const hkArray<hkpPhantom*>& hkpPhysicsSystem::getPhantoms() const {
+    return m_phantoms;
+}
+
+inline const hkArray<hkpConstraintInstance*>& hkpPhysicsSystem::getConstraints() const {
+    return m_constraints;
+}
+
+inline const hkArray<hkpAction*>& hkpPhysicsSystem::getActions() const {
+    return m_actions;
+}
+
+inline const char* hkpPhysicsSystem::getName() const {
+    return m_name;
+}
+
+inline void hkpPhysicsSystem::setName(const char* name) {
+    m_name = name;
+}
+
+inline hkUlong hkpPhysicsSystem::getUserData() const {
+    return m_userData;
+}
+
+inline void hkpPhysicsSystem::setUserData(hkUlong d) {
+    m_userData = d;
+}
+
+inline hkBool hkpPhysicsSystem::isActive() const {
+    return m_active;
+}
+
+inline void hkpPhysicsSystem::setActive(hkBool active) {
+    m_active = active;
+}
diff --git a/lib/hkStubs/Havok/Physics2012/Utilities/Serialize/hkpPhysicsData.h b/lib/hkStubs/Havok/Physics2012/Utilities/Serialize/hkpPhysicsData.h
new file mode 100644
index 00000000..4a29df4b
--- /dev/null
+++ b/lib/hkStubs/Havok/Physics2012/Utilities/Serialize/hkpPhysicsData.h
@@ -0,0 +1,78 @@
+#pragma once
+
+#include <Havok/Common/Base/hkBase.h>
+#include <Havok/Physics2012/Dynamics/World/hkpPhysicsSystem.h>
+#include <Havok/Physics2012/Dynamics/World/hkpWorldCinfo.h>
+
+class hkpRigidBody;
+class hkpWorld;
+
+class hkpPhysicsData : public hkReferencedObject {
+public:
+    HK_DECLARE_CLASS_ALLOCATOR(hkpPhysicsData)
+    HK_DECLARE_REFLECTION()
+
+    hkpPhysicsData();
+    explicit hkpPhysicsData(hkFinishLoadedObjectFlag f) : hkReferencedObject(f), m_systems(f) {}
+
+    ~hkpPhysicsData() override;
+
+    inline hkpWorldCinfo* getWorldCinfo();
+    inline void setWorldCinfo(hkpWorldCinfo* info);
+
+    inline void addPhysicsSystem(hkpPhysicsSystem* system);
+    inline void removePhysicsSystem(int i);
+    inline const hkArray<hkpPhysicsSystem*>& getPhysicsSystems() const;
+
+    hkpPhysicsSystem* findPhysicsSystemByName(const char* name) const;
+    /// Look for a rigid body by name (case insensitive)
+    hkpRigidBody* findRigidBodyByName(const char* name) const;
+
+    void populateFromWorld(const hkpWorld* world, bool saveContactPoints = false);
+
+    hkpWorld* createWorld(hkBool registerAllAgents = true);
+
+    struct SplitPhysicsSystemsOutput {
+        HK_DECLARE_CLASS_ALLOCATOR(hkpPhysicsData::SplitPhysicsSystemsOutput)
+
+        hkpPhysicsSystem* m_unconstrainedFixedBodies;
+        hkpPhysicsSystem* m_unconstrainedKeyframedBodies;
+        hkpPhysicsSystem* m_unconstrainedMovingBodies;
+        hkpPhysicsSystem* m_phantoms;
+        hkArray<hkpPhysicsSystem*> m_constrainedSystems;
+    };
+
+    static void splitPhysicsSystems(const hkpPhysicsSystem* inputSystemConst,
+                                    SplitPhysicsSystemsOutput& output);
+
+protected:
+    hkpWorldCinfo* m_worldCinfo;
+    hkArray<hkpPhysicsSystem*> m_systems;
+};
+
+inline hkpWorldCinfo* hkpPhysicsData::getWorldCinfo() {
+    return m_worldCinfo;
+}
+
+inline void hkpPhysicsData::setWorldCinfo(hkpWorldCinfo* info) {
+    if (info != nullptr)
+        info->addReference();
+    if (m_worldCinfo != nullptr)
+        m_worldCinfo->removeReference();
+
+    m_worldCinfo = info;
+}
+
+inline void hkpPhysicsData::addPhysicsSystem(hkpPhysicsSystem* system) {
+    system->addReference();
+    m_systems.pushBack(system);
+}
+
+inline void hkpPhysicsData::removePhysicsSystem(int i) {
+    m_systems[i]->removeReference();
+    m_systems.removeAt(i);
+}
+
+inline const hkArray<hkpPhysicsSystem*>& hkpPhysicsData::getPhysicsSystems() const {
+    return m_systems;
+}