Extra Grenades Pause the game and press R1, X, R1, >, Square, >, Square.

Extra Missles Pause the game and press X, Circle, R1, >, Triangle, X, Triangle.

Full Health Pause the game and press R1, Triangle, L1, <, Triangle, Circle, X.

Infinite Lives On the Drench, get as many 1-ups as you want, exit the level, save the game, and reset it. then, load the game and return to that level, and all the lives will be back where you left off. Repeat as desired.

Level Select Pause the game and press Up, <, Down, R2, >, Square, X.

Red Beam Mode Pause the game and press >, Up, <, Circle, Up, Circle, Circle.