diff --git a/CMakeLists.txt b/CMakeLists.txt
index d62c2b2b..6c408d65 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -21,6 +21,7 @@ add_library(lego1 SHARED
   LEGO1/buildingentity.cpp
   LEGO1/bumpbouy.cpp
   LEGO1/carrace.cpp
+  LEGO1/define.cpp
   LEGO1/dllmain.cpp
   LEGO1/dunebuggy.cpp
   LEGO1/elevatorbottom.cpp
diff --git a/LEGO1/define.cpp b/LEGO1/define.cpp
new file mode 100644
index 00000000..84073b9d
--- /dev/null
+++ b/LEGO1/define.cpp
@@ -0,0 +1,10 @@
+#include "define.h"
+
+// 0x10101eac
+const char *g_parseExtraTokens = ":;";
+
+// 0x10101edc
+const char *g_strWORLD = "WORLD";
+
+// 0x10102040
+const char *g_strACTION = "ACTION";
diff --git a/LEGO1/define.h b/LEGO1/define.h
new file mode 100644
index 00000000..ec41943e
--- /dev/null
+++ b/LEGO1/define.h
@@ -0,0 +1,8 @@
+#ifndef DEFINE_H
+#define DEFINE_H
+
+extern const char *g_parseExtraTokens;
+extern const char *g_strWORLD;
+extern const char *g_strACTION;
+
+#endif // DEFINE_H
\ No newline at end of file
diff --git a/LEGO1/extra.h b/LEGO1/extra.h
new file mode 100644
index 00000000..05ed5f07
--- /dev/null
+++ b/LEGO1/extra.h
@@ -0,0 +1,21 @@
+#ifndef EXTRA_H
+#define EXTRA_H
+
+// Items related to the Extra string of key-value pairs found in MxOb
+
+enum ExtraActionType
+{
+  ExtraActionType_opendisk = 1,
+  ExtraActionType_openram  = 2,
+  ExtraActionType_close    = 3,
+  ExtraActionType_start    = 4,
+  ExtraActionType_stop     = 5,
+  ExtraActionType_run      = 6,
+  ExtraActionType_exit     = 7,
+  ExtraActionType_enable   = 8,
+  ExtraActionType_disable  = 9,
+  ExtraActionType_notify   = 10,
+  ExtraActionType_unknown  = 11,
+};
+
+#endif // EXTRA_H
diff --git a/LEGO1/legoentity.cpp b/LEGO1/legoentity.cpp
index b8ed69f9..d2062946 100644
--- a/LEGO1/legoentity.cpp
+++ b/LEGO1/legoentity.cpp
@@ -1,5 +1,9 @@
 #include "legoentity.h"
 
+#include "legoomni.h"
+#include "legoutil.h"
+#include "define.h"
+
 DECOMP_SIZE_ASSERT(LegoEntity, 0x68)
 
 // OFFSET: LEGO1 0x1000c290
@@ -16,8 +20,37 @@ MxLong LegoEntity::Notify(MxParam &p)
   return 0;
 }
 
+// OFFSET: LEGO1 0x100107e0 STUB
+void LegoEntity::vtable18()
+{
+
+}
+
 // OFFSET: LEGO1 0x10010810 STUB
 void LegoEntity::Destroy()
 {
   // TODO
 }
+
+// OFFSET: LEGO1 0x10010e10
+void LegoEntity::ParseAction(char *p_extra)
+{
+  char copy[1024];
+  char actionValue[1024];
+  strcpy(copy, p_extra);
+
+  if (KeyValueStringParse(actionValue, g_strACTION, copy)) {
+    m_actionType = MatchActionString(strtok(actionValue, g_parseExtraTokens));
+
+    if (m_actionType != ExtraActionType_exit) {
+      char *token = strtok(NULL, g_parseExtraTokens);
+
+      m_actionArgString = new char[strlen(token) + 1];
+      strcpy(m_actionArgString, token);
+
+      if (m_actionType != ExtraActionType_run) {
+        m_actionArgNumber = atoi(strtok(NULL, g_parseExtraTokens));
+      }
+    }
+  }
+}
diff --git a/LEGO1/legoentity.h b/LEGO1/legoentity.h
index fdfe997f..9fbbb5bb 100644
--- a/LEGO1/legoentity.h
+++ b/LEGO1/legoentity.h
@@ -2,6 +2,7 @@
 #define LEGOENTITY_H
 
 #include "mxentity.h"
+#include "extra.h"
 
 // VTABLE 0x100d4858
 // SIZE 0x68 (probably)
@@ -31,7 +32,16 @@ class LegoEntity : public MxEntity
     return !strcmp(name, LegoEntity::ClassName()) || MxEntity::IsA(name);
   }
 
-  virtual void Destroy() override; // vtable+0x1c
+  virtual void vtable18(); // vtable+0x18
+  virtual void Destroy(); // vtable+0x1c
+  virtual void ParseAction(char *); // vtable+0x20
+
+protected:
+  // For tokens from the extra string that look like this:
+  // "Action:openram;\lego\scripts\Race\CarRaceR;0"
+  ExtraActionType m_actionType; // 0x5c
+  char *m_actionArgString; // 0x60
+  MxS32 m_actionArgNumber; // 0x64
 
 };
 
diff --git a/LEGO1/legoomni.cpp b/LEGO1/legoomni.cpp
index 0c84395e..bbc8258b 100644
--- a/LEGO1/legoomni.cpp
+++ b/LEGO1/legoomni.cpp
@@ -58,7 +58,7 @@ void MakeSourceName(char *p_output, const char *p_input)
 }
 
 // OFFSET: LEGO1 0x100b7050
-MxBool KeyValueStringParse(char *p_outputValue, char *p_key, char *p_source)
+MxBool KeyValueStringParse(char *p_outputValue, const char *p_key, const char *p_source)
 {
   MxBool didMatch = FALSE;
 
diff --git a/LEGO1/legoomni.h b/LEGO1/legoomni.h
index be289769..a9cce9cf 100644
--- a/LEGO1/legoomni.h
+++ b/LEGO1/legoomni.h
@@ -113,6 +113,6 @@ __declspec(dllexport) MxLong Start(MxDSAction *a);
 LegoBuildingManager* BuildingManager();
 Isle* GetIsle();
 LegoPlantManager* PlantManager();
-MxBool KeyValueStringParse(char *, char *, char *);
+MxBool KeyValueStringParse(char *, const char *, const char *);
 
 #endif // LEGOOMNI_H
diff --git a/LEGO1/legoutil.cpp b/LEGO1/legoutil.cpp
index bac8f284..9827b376 100644
--- a/LEGO1/legoutil.cpp
+++ b/LEGO1/legoutil.cpp
@@ -2,6 +2,36 @@
 
 #include "mxtypes.h"
 
+#include <string.h>
+
+// OFFSET: LEGO1 0x1003e300
+ExtraActionType MatchActionString(const char *p_str) {
+  ExtraActionType result = ExtraActionType_unknown;
+
+  if (!strcmpi("openram", p_str))
+    result = ExtraActionType_openram;
+  else if (!strcmpi("opendisk", p_str))
+    result = ExtraActionType_opendisk;
+  else if (!strcmpi("close", p_str))
+    result = ExtraActionType_close;
+  else if (!strcmpi("start", p_str))
+    result = ExtraActionType_start;
+  else if (!strcmpi("stop", p_str))
+    result = ExtraActionType_stop;
+  else if (!strcmpi("run", p_str))
+    result = ExtraActionType_run;
+  else if (!strcmpi("exit", p_str))
+    result = ExtraActionType_exit;
+  else if (!strcmpi("enable", p_str))
+    result = ExtraActionType_enable;
+  else if (!strcmpi("disable", p_str))
+    result = ExtraActionType_disable;
+  else if (!strcmpi("notify", p_str))
+    result = ExtraActionType_notify;
+
+  return result;
+}
+
 // OFFSET: LEGO1 0x1003eae0
 void ConvertHSVToRGB(float h, float s, float v, float *r_out, float *b_out, float *g_out)
 {
diff --git a/LEGO1/legoutil.h b/LEGO1/legoutil.h
index 6a0113e8..b736cd29 100644
--- a/LEGO1/legoutil.h
+++ b/LEGO1/legoutil.h
@@ -1,6 +1,8 @@
 #ifndef LEGOUTIL_H
 #define LEGOUTIL_H
 
+#include "extra.h"
+
 template <class T>
 inline T Abs(T p_t)
 {
@@ -19,6 +21,7 @@ inline T Max(T p_t1, T p_t2)
   return p_t1 > p_t2 ? p_t1 : p_t2;
 }
 
+ExtraActionType MatchActionString(const char *);
 void ConvertHSVToRGB(float r, float g, float b, float* out_r, float* out_g, float* out_b);
 
 #endif // LEGOUTIL_H
diff --git a/LEGO1/mxentity.cpp b/LEGO1/mxentity.cpp
index 65adad67..54e854ab 100644
--- a/LEGO1/mxentity.cpp
+++ b/LEGO1/mxentity.cpp
@@ -1,6 +1,8 @@
 #include "mxentity.h"
 
-DECOMP_SIZE_ASSERT(MxEntity, 0x68)
+// Size subject to change. It's not clear yet which members belong to
+// MxEntity and which belong only the subclasses.
+DECOMP_SIZE_ASSERT(MxEntity, 0x5c)
 
 // OFFSET: LEGO1 0x1001d190
 MxEntity::MxEntity()
diff --git a/LEGO1/mxentity.h b/LEGO1/mxentity.h
index 25e74d1b..3d73292e 100644
--- a/LEGO1/mxentity.h
+++ b/LEGO1/mxentity.h
@@ -31,7 +31,7 @@ class MxEntity : public MxCore
 private:
   MxS32 m_mxEntityId; // 0x8
   MxAtomId m_atom; // 0xc
-  undefined m_unk10[0x58];
+  undefined m_unk10[76];
 };
 
 #endif // MXENTITY_H
diff --git a/LEGO1/mxpresenter.cpp b/LEGO1/mxpresenter.cpp
index 940248a0..b57af821 100644
--- a/LEGO1/mxpresenter.cpp
+++ b/LEGO1/mxpresenter.cpp
@@ -7,15 +7,10 @@
 #include <string.h>
 
 #include "decomp.h"
+#include "define.h"
 
 DECOMP_SIZE_ASSERT(MxPresenter, 0x40);
 
-// 0x10101eac
-char *g_parseExtraTokens = ":;";
-
-// 0x10101edc
-char *g_strWORLD = "WORLD";
-
 // OFFSET: LEGO1 0x100b4d50
 void MxPresenter::Init()
 {