Cheat menu:
Pause your game and press A + B, C(2), A(2), B(2), B + C.

Invincibility:
Pause your game and press A + B, A + B, C, A, Right(2), Left, Right.

View map:
Pause your game and press A + B, C(3), A, B(3).

Continue:
Pause your game and press A + Down, A + Down, A + Left, A + Right, B, C(2), B + C.

Continue (alternate):
Pause your game and press A + Right, B + Up, A, C(2), B, C, A. REMEMBER: This code may only be enabled once per game.

Extra life:
Pause your game and press A + Up, B, A, C, A(2), C, B.

Extra life (alternate):
Pause your game and press A, B, C(2), A(2), C, B. REMEMBER: This code may only be enabled once per game.

Full energy:
Pause your game and press A + C, B(2), C(3), A, B.

Full energy (alternate):
Pause your game and press A, C, B, C, B, A(2), C. REMEMBER: This code may only be enabled once per game.

Full ammunition:
Pause your game and press A + C, A, B, C, B, C, A, C(2).

Full ammunition (alternate):
Pause your game and press A, B, C, B, C, A, C(2). REMEMBER: This code may only be enabled once per game.

Homing missiles:
Pause your game and press Right + A, A(2), B, A, C, B, A.

Homing missiles (alternate):
Pause your game and press A(2), C, B, A, C(3). REMEMBER: This code may only be enabled once per game.

Plasma weapon:
Pause your game and press C + Up, A(2), C, A, B, C(2).

Plasma weapon (alternate):
Pause your game and press C, A, B, C, A, B, C(2). REMEMBER: This code may only be enabled once per game.

View ending sequence:
Pause your game and press A + C, A + C, A + C, A, B, C, B, A.

Level skip:
Pause your game and press B(2), A, C, A + B, A + B, A + B, A + B.