Press ~ while playing, enter one of the following codes, then press [Enter] to activate the corresponding cheat function.

Effect - Cheat Code

Activate all codes - GiveMeAll
Full lives - MoreLives
Refill health - HealthMe
Invincible for 30 seconds - GiveMeInvulnerable
Invisible for 30 seconds - GiveMeInvisibility
All guns, rockets, missiles, lasers, plasma cannons and nuke - GiveMeAllAmmo
Refill fuel - GiveMeFuel