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

Heavy weapon

99 heavy ammo

Fix selected toy

Switch machine gun

All Levels Completed

Hidden Levels

X, A, Y, B, A, X

A, B, X, Y, B, A

A, X, B, Y, A, Y

B, A, Y, X, A, B

Y, X, B, A, A, B

A, B, Y, X, Y, X