Pause the game. Now hold L and enter the following codes. You’ll hear
music to confirm entry:

Enable all maps      A, Y, X, B, Y, X 

Heavy weapon         X, A, Y, B, A, X

99 heavy ammo        A, B, X, Y, B, A

Fix selected toy     A, X, B, Y, A, Y

Switch machine gun   B, A, Y, X, A, B

All Levels Completed Y, X, B, A, A, B

Hidden Levels        A, B, Y, X, Y, X

 

Thanks to Revolution readers Kirk Watts, Adam Martindale and Monty Montgomery!