diff --git a/CMakeLists.txt b/CMakeLists.txt
index 3a47fc78..d96b0c61 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -109,6 +109,7 @@ add_library(lego1 SHARED
   LEGO1/mxdiskstreamprovider.cpp
   LEGO1/mxdisplaysurface.cpp
   LEGO1/mxdsaction.cpp
+  LEGO1/mxdsactionlist.cpp
   LEGO1/mxdsanim.cpp
   LEGO1/mxdschunk.cpp
   LEGO1/mxdsevent.cpp
diff --git a/LEGO1/mxdsactionlist.cpp b/LEGO1/mxdsactionlist.cpp
new file mode 100644
index 00000000..86c75365
--- /dev/null
+++ b/LEGO1/mxdsactionlist.cpp
@@ -0,0 +1,21 @@
+#include "mxdsactionlist.h"
+#include "mxdsaction.h"
+
+DECOMP_SIZE_ASSERT(MxDSActionList, 0x1c);
+
+// OFFSET: LEGO1 0x100c9c90
+MxS8 MxDSActionList::Compare(MxDSAction *p_var0, MxDSAction *p_var1)
+{
+  if (p_var1 == p_var0)
+    return 0;
+  if (p_var1 <= p_var0)
+    return 1;
+  return -1;
+}
+
+// OFFSET: LEGO1 0x100c9cb0
+void MxDSActionList::Destroy(MxDSAction *p_action)
+{
+  if (p_action)
+    delete p_action;
+}
\ No newline at end of file
diff --git a/LEGO1/mxdsactionlist.h b/LEGO1/mxdsactionlist.h
new file mode 100644
index 00000000..4ae6e2a6
--- /dev/null
+++ b/LEGO1/mxdsactionlist.h
@@ -0,0 +1,28 @@
+#ifndef MXDSACTIONLIST_H
+#define MXDSACTIONLIST_H
+
+#include "decomp.h"
+#include "mxlist.h"
+
+class MxDSAction;
+
+// VTABLE 0x100dced8
+// SIZE 0x1c
+class MxDSActionList : public MxList<MxDSAction>
+{
+public:
+  MxDSActionList() {
+    this->m_unk18 = 0;
+  }
+
+  virtual MxS8 Compare(MxDSAction *, MxDSAction *); // +0x14
+
+  static void Destroy(MxDSAction *p_action);
+
+private:
+  undefined m_unk18;
+};
+
+typedef MxListCursorChild<MxDSAction> MxDSActionListCursor;
+
+#endif // MXDSACTIONLIST_H
diff --git a/LEGO1/mxdsmultiaction.cpp b/LEGO1/mxdsmultiaction.cpp
index 0328a5fd..6cbccc39 100644
--- a/LEGO1/mxdsmultiaction.cpp
+++ b/LEGO1/mxdsmultiaction.cpp
@@ -5,12 +5,42 @@ DECOMP_SIZE_ASSERT(MxDSMultiAction, 0x9c)
 // OFFSET: LEGO1 0x100c9b90
 MxDSMultiAction::MxDSMultiAction()
 {
-  // TODO
   this->SetType(MxDSType_MultiAction);
+  this->m_actions = new MxDSActionList;
+  this->m_actions->SetDestroy(MxDSActionList::Destroy);
 }
 
-// OFFSET: LEGO1 0x100ca060 STUB
+// OFFSET: LEGO1 0x100ca060
 MxDSMultiAction::~MxDSMultiAction()
 {
-  // TODO
+  if (this->m_actions)
+    delete this->m_actions;
 }
+
+// OFFSET: LEGO1 0x100ca5e0
+undefined4 MxDSMultiAction::unk14()
+{
+  undefined4 result = MxDSAction::unk14();
+
+  MxDSActionListCursor cursor(this->m_actions);
+  MxDSAction *action;
+  while (cursor.Next(action))
+    result += action->unk14();
+
+  return result;
+}
+
+// OFFSET: LEGO1 0x100ca6c0
+MxU32 MxDSMultiAction::GetSizeOnDisk()
+{
+  MxU32 totalSizeOnDisk = MxDSAction::GetSizeOnDisk() + 16;
+
+  MxDSActionListCursor cursor(this->m_actions);
+  MxDSAction *action;
+  while (cursor.Next(action))
+    totalSizeOnDisk += action->GetSizeOnDisk();
+
+  this->m_sizeOnDisk = totalSizeOnDisk - MxDSAction::GetSizeOnDisk();
+
+  return totalSizeOnDisk;
+}
\ No newline at end of file
diff --git a/LEGO1/mxdsmultiaction.h b/LEGO1/mxdsmultiaction.h
index 6e049965..7d4312f4 100644
--- a/LEGO1/mxdsmultiaction.h
+++ b/LEGO1/mxdsmultiaction.h
@@ -2,7 +2,7 @@
 #define MXDSMULTIACTION_H
 
 #include "mxdsaction.h"
-#include "decomp.h"
+#include "mxdsactionlist.h"
 
 // VTABLE 0x100dcef0
 // SIZE 0x9c
@@ -25,8 +25,12 @@ class MxDSMultiAction : public MxDSAction
     return !strcmp(name, MxDSMultiAction::ClassName()) || MxDSAction::IsA(name);
   }
 
-  undefined4 m_unk0x94;
-  undefined4 m_unk0x98;
+  virtual undefined4 unk14(); // vtable+14;
+  virtual MxU32 GetSizeOnDisk(); // vtable+18;
+
+private:
+  MxU32 m_sizeOnDisk;
+  MxDSActionList *m_actions;
 };
 
 #endif // MXDSMULTIACTION_H
diff --git a/LEGO1/mxlist.h b/LEGO1/mxlist.h
index 013ef852..a4231c92 100644
--- a/LEGO1/mxlist.h
+++ b/LEGO1/mxlist.h
@@ -60,6 +60,7 @@ class MxList : protected MxListParent<T>
 
   void Append(T*);
   MxU32 GetCount() { return m_count; }
+  void SetDestroy(void (*p_customDestructor)(T *)) { this->m_customDestructor = p_customDestructor; }
 
   friend class MxListCursor<T>;