Walls on map:
Press LS, RS(2), A, Left(2), Up, A, C at the auto-map screen while playing the game. Do not pause the game. You will hear a sound if you have entered the code correctly. All walls will be displayed on the map.

Full map:
Press LS, RS(2), Right, Up, B(2), Left, RS at the auto-map screen while playing the game. Do not pause the game. You will hear a sound if you have entered the code correctly. All items will be displayed on the map.

Invincibility:
Press Up, Right, A, B, A, Down, A, LS(2) at the auto-map screen while playing the game. Do not pause the game. You will hear a sound if you have entered the code correctly.

Weapons and ammo:
Press A, Left, A, B, A, Right, A, C, A at the auto-map screen while playing the game. Do not pause the game. You will hear a sound if you have entered the code correctly. All weapons and 500 rounds of ammunition will be available.

Level select:
Press LS, Up, C(2), RS, Down, A, Left(2) at the auto-map screen while playing the game. Do not pause the game. You will hear a sound if you have entered the code correctly. Restart the game for access to any level.

Screen size:
Press Up, Right, LS, Up, Right(2), RS, A, Left at the auto-map screen while playing the game. Do not pause the game. You will hear a sound if you have entered the code correctly. The game may now be set to run in two additional larger screen sizes, including full screen.

Saved game bug:
The 3DO Memory Manager will lock up or reset when deleting the saved game file named "DOOM.PREFS". It will also be unable to display any files below this file. The file may be deleted by using the built-in memory managers of Syndicate or Wing Commander III.