God Mode:
During gameplay pause the game, then hold R and L and press A, A, B, A, A, A, A, A.

All weapons, keys, Items:
During gameplay pause the game, then hold R and L and press A, B, B, A, A, A, A, A.

Level Skip:
If you are totally stuck on a level, then use this cheat to skip it all together. Pause the game, hold L + R and press A, B, A, A, B, B, B, and then A. The word loading will appear if you got it right.

Invincibility:
During gameplay pause the game, then hold R and L and press B, B, B, A, A, A, A, A.

Computer Map:
During gameplay pause the game, then hold R and L and press B, A, A, A, A, A, A, A.

Berserk Mode:
During gameplay pause the game, then hold R and L and press B, A, B, A, A, A, A, A.

Radiation Suit:
During gameplay pause the game, then hold R and L and press B, B, A, A, A, A, A, A.

Thanks to Revolution readers Symbiode and Ben Alqadhi!