Today we’ve preserved a very special piece of software, a post release debug build of Mario Kart: Double Dash!! This build served some sort of purpose at Nintendo’s Research & Engineering Division (commonly referred to as NCL RED). It’s dated roughly half a year after the retail game’s release, so it’s purpose is currently unknown. Although one thing that should be noted is that it contains many debug functions within and can be enabled by the player!



  • Contains a build date on the Nintendo bootup screen (Mon Jul 5 13:04:10 2004)
  • Various debug menus can be enabled via button combinations.
  • Debugging symbols are intact.

Debug Menus

  • Z + Start to open main debug menu (can only be enabled on title and menus outside of a race).
  • Pressing Y on the LAN screen brings up various bits of debug info.
  • Pressing L + D-Pad Down mutes the BGM.


The following debug functions can be enabled by plugging in and using a second controller into the GameCube:

  • R+Z to enable or disable debug info screen
  • L/R to change between Usr Page, Mem Map, Proc Time
Usr Page: 
    Use C-Stick Left and Right to change page
    has more info during race
Proc Time: 
    C-stick to start or stop a timer for measurement. 
    Press Y to toggle extra info (e.g. during race)
Mem Map: 
    C-stick Up/Down to select an item, 
    Press A to view more details about the item in Heap Spec.
    Hold Start, makes green/red bar at bottom bigger (shows System Heap in more detail?)
Heap Spec:
    Press B to return back to Mem Map
    C-stick left/right are supposed to decrement/increment some value.


ROM Information

----| File Data |--------------------------------------------------
System:             Nintendo - Nintendo GameCube        
File:               GM4E01.iso
BitSize:            10 Gbit
Size (Bytes):       1459978240
CRC32:              2477E93F
MD5:                F1C8CD08BEA08E16AC8F526FB259017D
SHA1:               AA9341AB5DABCA27BC829A5FD8E9C535B11E166A
SHA256:             3A31632C56B6121C0E718AED6F3C2DB0583A0C2540D4FFA5159CBF984E7D651B
----| Header Data |------------------------------------------------
Game Title:         43 2004.07.05 MarioKartUM.gcm
Game Serial:        GM4E (USA)
Maker Code:         01 (Nintendo)
Version:            0x00 (v1.0)
Disc Id:            1

Disc Images

Disc Front

Overview Video


Download Mario Kart - Double Dash!! (USA) (Prototype)