diff --git a/LEGO1/mxdsaction.h b/LEGO1/mxdsaction.h
index a677741c..2d177f8f 100644
--- a/LEGO1/mxdsaction.h
+++ b/LEGO1/mxdsaction.h
@@ -55,7 +55,7 @@ class MxDSAction : public MxDSObject
   MxU16 m_unkLength;
   undefined4 m_unk84;
   undefined4 m_unk88;
-  MxOmni* m_omni; // 0x8c
+  MxOmni *m_omni; // 0x8c
   MxLong m_someTimingField; // 0x90
 };
 
diff --git a/LEGO1/mxdsmediaaction.cpp b/LEGO1/mxdsmediaaction.cpp
index a8acde30..d368aa3d 100644
--- a/LEGO1/mxdsmediaaction.cpp
+++ b/LEGO1/mxdsmediaaction.cpp
@@ -1,21 +1,103 @@
 #include "mxdsmediaaction.h"
 
+DECOMP_SIZE_ASSERT(MxDSMediaAction, 0xb8)
+
 // OFFSET: LEGO1 0x100c8b40
 MxDSMediaAction::MxDSMediaAction()
 {
-  this->m_unk98 = 0;
+  this->m_mediaSrcPath = NULL;
   this->m_unk9c = 0;
   this->m_unka0 = 0;
-  this->m_unka4 = 0;
-  this->m_unka8 = 0;
-  this->m_unkac = 1;
-  this->m_unkb4 = 0xffffffff;
-  this->m_unkb0 = 0;
+  this->m_framesPerSecond = 0;
+  this->m_mediaFormat = 0;
+  this->m_paletteManagement = 1;
+  this->m_unkb4 = -1;
+  this->m_sustainTime = 0;
   this->SetType(MxDSType_MediaAction);
 }
 
 // OFFSET: LEGO1 0x100c8cf0
 MxDSMediaAction::~MxDSMediaAction()
 {
-  delete this->m_unk98;
+  delete[] this->m_mediaSrcPath;
 }
+
+// OFFSET: LEGO1 0x100c8d60
+void MxDSMediaAction::CopyFrom(MxDSMediaAction &p_dsMediaAction)
+{
+  CopyMediaSrcPath(p_dsMediaAction.m_mediaSrcPath);
+
+  // TODO
+  this->m_unk9c = p_dsMediaAction.m_unk9c;
+  this->m_unka0 = p_dsMediaAction.m_unka0;
+
+  this->m_framesPerSecond = p_dsMediaAction.m_framesPerSecond;
+  this->m_mediaFormat = p_dsMediaAction.m_mediaFormat;
+  this->m_paletteManagement = p_dsMediaAction.m_paletteManagement;
+  this->m_sustainTime = p_dsMediaAction.m_sustainTime;
+}
+
+// OFFSET: LEGO1 0x100c8dc0
+MxDSMediaAction &MxDSMediaAction::operator=(MxDSMediaAction &p_dsMediaAction)
+{
+  if (this == &p_dsMediaAction)
+    return *this;
+
+  MxDSAction::operator=(p_dsMediaAction);
+  this->CopyFrom(p_dsMediaAction);
+  return *this;
+}
+
+// OFFSET: LEGO1 0x100c8f10
+MxU32 MxDSMediaAction::GetSizeOnDisk()
+{
+  MxU32 totalSizeOnDisk = MxDSAction::GetSizeOnDisk();
+
+  if (this->m_mediaSrcPath)
+    totalSizeOnDisk += strlen(this->m_mediaSrcPath) + 1;
+  else
+    totalSizeOnDisk++;
+
+  totalSizeOnDisk += 24;
+  this->m_sizeOnDisk = totalSizeOnDisk - MxDSAction::GetSizeOnDisk();
+  return totalSizeOnDisk;
+}
+
+// OFFSET: LEGO1 0x100c8f60
+void MxDSMediaAction::Deserialize(char **p_source, MxS16 p_unk24)
+{
+  MxDSAction::Deserialize(p_source, p_unk24);
+
+  CopyMediaSrcPath(*p_source);
+  *p_source += strlen(this->m_mediaSrcPath) + 1;
+  
+  this->m_unk9c = *(undefined4*) *p_source;
+  *p_source += sizeof(undefined4);
+  this->m_unka0 = *(undefined4*) *p_source;
+  *p_source += sizeof(undefined4);
+  this->m_framesPerSecond = *(MxS32*) *p_source;
+  *p_source += sizeof(MxS32);
+  this->m_mediaFormat = *(MxS32*) *p_source;
+  *p_source += sizeof(MxS32);
+  this->m_paletteManagement = *(MxS32*) *p_source;
+  *p_source += sizeof(MxS32);
+  this->m_sustainTime = *(MxLong*) *p_source;
+  *p_source += sizeof(MxLong);
+}
+
+// OFFSET: LEGO1 0x100c8e80
+void MxDSMediaAction::CopyMediaSrcPath(const char *p_mediaSrcPath)
+{
+  if (this->m_mediaSrcPath == p_mediaSrcPath)
+    return;
+
+  delete[] this->m_mediaSrcPath;
+
+  if (p_mediaSrcPath) {
+    this->m_mediaSrcPath = new char[strlen(p_mediaSrcPath) + 1];
+    if (this->m_mediaSrcPath)
+      strcpy(this->m_mediaSrcPath, p_mediaSrcPath);
+  }
+  else
+    this->m_mediaSrcPath = NULL;
+}
\ No newline at end of file
diff --git a/LEGO1/mxdsmediaaction.h b/LEGO1/mxdsmediaaction.h
index 5e6a6141..1ebbfdd2 100644
--- a/LEGO1/mxdsmediaaction.h
+++ b/LEGO1/mxdsmediaaction.h
@@ -12,6 +12,9 @@ class MxDSMediaAction : public MxDSAction
   MxDSMediaAction();
   virtual ~MxDSMediaAction() override;
 
+  void CopyFrom(MxDSMediaAction &p_dsMediaAction);
+  MxDSMediaAction &operator=(MxDSMediaAction &p_dsMediaAction);
+
   // OFFSET: LEGO1 0x100c8be0
   inline virtual const char *ClassName() const override // vtable+0x0c
   {
@@ -24,16 +27,21 @@ class MxDSMediaAction : public MxDSAction
   {
     return !strcmp(name, MxDSMediaAction::ClassName()) || MxDSAction::IsA(name);
   }
+
+  virtual MxU32 GetSizeOnDisk(); // vtable+18;
+  virtual void Deserialize(char **p_source, MxS16 p_unk24); // vtable+1c;
+
+  void CopyMediaSrcPath(const char *p_mediaSrcPath);
 private:
-  MxS32* m_unk94;
-  MxS32* m_unk98;
-  MxS32* m_unk9c;
-  MxS32* m_unka0;
-  MxS32* m_unka4;
-  MxS32* m_unka8;
-  MxS32 m_unkac;
-  MxS32* m_unkb0;
-  MxS32 m_unkb4;
+  MxU32 m_sizeOnDisk;
+  char *m_mediaSrcPath;
+  undefined4 m_unk9c;
+  undefined4 m_unka0;
+  MxS32 m_framesPerSecond;
+  MxS32 m_mediaFormat;
+  MxS32 m_paletteManagement;
+  MxLong m_sustainTime;
+  undefined4 m_unkb4;
 };
 
 #endif // MXDSMEDIAACTION_H