Debug mode
When "Push Start Button" is flashing on the opening screen, hold Z and press Right, Left, Up, Down, A, B, Start. Then, a debug menu that allows stage select and other effects will appear.

Level select
When "Push Start Button" is flashing on the opening screen, press C-Up(7).

Power chopper
At the main menu, hold L + R + Z and press Start before selecting a chopper.

Shoot down the President
While playing the game, press Z + C-Up + C-Down, then launch a homing cluster at your opponent. If it hits, you will see the president jump out of the plane.