Pause the game and press Y, A, B*2, A, Y, A,B*2, A.
Eight plasma shots
Pause the game and press A*2, B + L, A*2, X,B + L, X.
Extra Continue
Pause the game and press A, B, A, B, X, Y,X, Y.
Extra Life
Pause game play and press B + X, B*3, A*2,X, A.
Fill Up Life Bar
Pause the game and press A + X, B, A, B*2, X + Y,B, A.
Full Ammo
Pause the game and press A, B, B + L, B, X,A, X*2.
Level Skip
When you enter a level press start so the game pauses. After you do that do the following code as fast as you can a, b, x, a, a + x, b + x, b + x, a + x. Once you do this you will see Jim and the title to the next level. You can do this as many times as you like on any level.
See the Map
Pause the game and press A, X, A, X, A*4.
The Princess
Pause the game and press Left + A, X*2, X + B, X,A, X, Left + A.
To Get Cheat Mode
Pause the game and press Left + A, B, X, A*2, B, X, A, Start. An information screen will appear allowing invincibility, level select, pausing without a dim screen(wow), or viewing the entirelevel. Note: Using this code may prevent completion ofthe game.
Another cheat code...