diff --git a/compiled/ext.c b/compiled/ext.c
index e69de29..49084ec 100644
--- a/compiled/ext.c
+++ b/compiled/ext.c
@@ -0,0 +1 @@
+void __attribute__((naked)) cpufastset(void *source, void *dest, int mode) {}
diff --git a/compiled/vwf.h b/compiled/vwf.h
index 1b79ea1..111e5e8 100644
--- a/compiled/vwf.h
+++ b/compiled/vwf.h
@@ -1,5 +1,6 @@
 typedef unsigned char byte;
 #define QUESTION_MARK 0x1F;
+#define CPUFASTSET_FILL (0x1000000)
 
 unsigned short *tile_offset = (unsigned short*)0x30051EC;
 unsigned short *palette_mask = (unsigned short*)0x3005228;
@@ -19,3 +20,5 @@ extern const byte m2_nybbles_to_bits[];
 extern const byte *m2_font_table[];
 extern const byte m2_font_heights[];
 extern unsigned short const *m2_widths_table[];
+
+extern void cpufastset(void *source, void *dest, int mode);
diff --git a/m2-hack.asm b/m2-hack.asm
index d166fd3..54ff013 100644
--- a/m2-hack.asm
+++ b/m2-hack.asm
@@ -579,6 +579,7 @@ m2_enemy_attributes:
 //==============================================================================
 
 .org 0x80FCE6C
+.include "syscalls.asm"
 .include "m2-vwf.asm"
 .include "m2-vwf-entries.asm"
 .include "m2-formatting.asm"
diff --git a/syscalls.asm b/syscalls.asm
new file mode 100644
index 0000000..a290973
--- /dev/null
+++ b/syscalls.asm
@@ -0,0 +1,3 @@
+cpufastset:
+swi     0xC
+bx      lr