Level Skip
Press Start to pause game play in single player games then hold L + R and press A, B, A, A, B, B, B, A. ‘Loading’ will appear on screen if the comination entered was correct.
Advance Ten Levels
Advance ten levels depending on your current level by pressing Start to pause game play in single player games then hold L + R and press:
A, B, A, A, B, B, A, A.

Computer Map
Press Start to pause game play then hold L + R and press:
B, A, A, A, A, A, A, A.
Radiation Suit
Press Start to pause game play, then hold L + R and press:
B, B, A, A, A, A, A, A.
All Weapons, Items, Keys
Press Start to pause game play then hold L + R and press:
A, B, B, A, A, A, A, A.

God Mode
Press Start to pause game play then hold L + R and press:
A, A, B, A, A, A, A, A.

Disable God Mode
Press Start to pause game play then hold L + R and press:
A, A, B, A, B, B, B, B.

Berserk
Press Start to pause game play, then hold L + R and press:
B, A, B, A, A, A, A, A.

Invincibility
Press Start to pause game play then hold L + R and press:
B, B, B, A, A, A, A, A.