Highlight the "Class And Track" option at the main menu, hold L + R + Down, and press 2*X, 2*Y, 2*Z.
Machine Gun
Hold L + R + Down and press 2*X during game play.
Phantom Class
Highlight the "Class And Track" option at the main menu, hold L + R + Down, and press 2*A, 2*B, 2*C.
Piranha Team
Highlight the "Team" option at the main menu, hold L + R + Down, and press A, X, B, Y, C, Z.
Strange Ships
Hold L + R + Down when the Saturn logo appears. Release the buttons at the title screen. The vehicles will be changed to a bee, snail, pig, flying saucer, and shark.
Unlimited Auto-Pilot
Hold L + R + Down and press X, Y, Z, X, Y, Z, X, Y, Z during game play.
All Tracks...