diff --git a/LEGO1/mxdsmultiaction.h b/LEGO1/mxdsmultiaction.h
index 1689cc2d..4e516333 100644
--- a/LEGO1/mxdsmultiaction.h
+++ b/LEGO1/mxdsmultiaction.h
@@ -37,10 +37,8 @@ public:
   virtual MxBool HasId(MxU32 p_objectId) override; // vtable+34;
   virtual void SetSomeTimingField(MxLong p_someTimingField) override; // vtable+38;
 
-private:
-  MxU32 m_sizeOnDisk;
-
 protected:
+  MxU32 m_sizeOnDisk;
   MxDSActionList *m_actions;
 };
 
diff --git a/LEGO1/mxdsselectaction.cpp b/LEGO1/mxdsselectaction.cpp
index 58af9543..e49f587a 100644
--- a/LEGO1/mxdsselectaction.cpp
+++ b/LEGO1/mxdsselectaction.cpp
@@ -1,4 +1,7 @@
 #include "mxdsselectaction.h"
+#include "mxvariabletable.h"
+#include "mxtimer.h"
+#include "mxomni.h"
 
 DECOMP_SIZE_ASSERT(MxDSSelectAction, 0xb0)
 
@@ -48,4 +51,81 @@ MxDSAction *MxDSSelectAction::Clone()
     *clone = *this;
 
   return clone;
+}
+
+// OFFSET: LEGO1 0x100cbe10
+MxU32 MxDSSelectAction::GetSizeOnDisk()
+{
+  MxU32 totalSizeOnDisk = MxDSParallelAction::GetSizeOnDisk();
+
+  totalSizeOnDisk += strlen(this->m_unk0x9c.GetData()) + 1;
+
+  MxStringListCursor cursor(this->m_unk0xac);
+  MxString string;
+  while (cursor.Next(string))
+    totalSizeOnDisk += strlen(string.GetData()) + 1;
+
+  // Note: unlike the other classes, MxDSSelectAction does not have its own
+  // sizeOnDisk member. Instead, it overrides the one from MxDSMultiAction.
+  this->m_sizeOnDisk = totalSizeOnDisk;
+
+  return totalSizeOnDisk;
+}
+
+// OFFSET: LEGO1 0x100cbf60
+void MxDSSelectAction::Deserialize(char **p_source, MxS16 p_unk24)
+{
+  MxString string;
+  MxDSAction::Deserialize(p_source, p_unk24);
+
+  MxU32 extraFlag = *(MxU32*)(*p_source + 4) & 1;
+  *p_source += 12;
+
+  this->m_unk0x9c = *p_source;
+
+  if (!strnicmp(this->m_unk0x9c.GetData(), "RANDOM_", strlen("RANDOM_"))) {
+    char buffer[10];
+    MxS16 value = atoi(&this->m_unk0x9c.GetData()[strlen("RANDOM_")]);
+
+    srand(Timer()->GetTime());
+    MxS32 random = rand() % value;
+    string = itoa((MxS16) random, buffer, 10);
+  }
+  else
+    string = VariableTable()->GetVariable(*p_source);
+
+  *p_source += strlen(*p_source) + 1;
+
+  MxU32 count = *(MxU32*) *p_source;
+  *p_source += sizeof(MxU32);
+
+  if (count) {
+    MxS32 index = -1;
+    this->m_unk0xac->DeleteAll();
+
+    MxU32 i;
+    for (i = 0; i < count; i++) {
+      if (!strcmp(string.GetData(), *p_source))
+        index = i;
+
+      this->m_unk0xac->OtherAppend(*p_source);
+      *p_source += strlen(*p_source) + 1;
+    }
+
+    for (i = 0; i < count; i++) {
+      MxU32 extraFlag = *(MxU32*)(*p_source + 4) & 1;
+      *p_source += 8;
+
+      MxDSAction *action = (MxDSAction*) DeserializeDSObjectDispatch(p_source, p_unk24);
+
+      if (index == i)
+        this->m_actions->Append(action);
+      else
+        delete action;
+
+      *p_source += extraFlag;
+    }
+  }
+
+  *p_source += extraFlag;
 }
\ No newline at end of file
diff --git a/LEGO1/mxdsselectaction.h b/LEGO1/mxdsselectaction.h
index 746afc87..7b668a15 100644
--- a/LEGO1/mxdsselectaction.h
+++ b/LEGO1/mxdsselectaction.h
@@ -29,9 +29,8 @@ public:
     return !strcmp(name, MxDSSelectAction::ClassName()) || MxDSParallelAction::IsA(name);
   }
 
-  //virtual MxU32 GetSizeOnDisk() override; // vtable+18;
-  //virtual void Deserialize(char **p_source, MxS16 p_unk24) override; // vtable+1c;
-  //virtual MxLong GetDuration() override; // vtable+24;
+  virtual MxU32 GetSizeOnDisk() override; // vtable+18;
+  virtual void Deserialize(char **p_source, MxS16 p_unk24) override; // vtable+1c;
   virtual MxDSAction *Clone() override; // vtable+2c;
 
 private: