God mode:
Pause, then press Up, Down, Left, Right, Left Trigger, Right Trigger, Left, Right, Start.
Extra Lives:
Pause, then press A, B, X, Y, Left Trigger, Right Trigger, Up, Down, Left, Right.
Instant Win:
Pause, then press Left Trigger, Right Trigger, Left Trigger, Right Trigger, Left, Right, Left, Right, Y, X.
Grenades:
Pause, then press Down, Down, Down, Down, Down, Up, Up, Up, Up, Right Trigger.
Level Select:
Pause, then press Up, Down, Up, Down, Up, Down, Left, Right, Right, Y.
Level Skip:
Pause, then press Y, Y, X, X, Left Trigger, Right Trigger, Down, Down, Up, Up.
Shields:
Pause, then press Up, Down, Left, Right, X, Up, Down, Left, Right, Y.
Credits:
Pause, then press A, B, Left, A, B, Right, B, A, Down, Right Trigger.
EasterEgg:
Pause, then press Left Trigger, Left, Right Trigger, Right, X, X,
Down, Down, Right Trigger, Left Trigger.
Get the best selection of
Expendable Cheats, Codes & Walkthrough/Guide/FAQ for Dreamcast from Cheat Code Central
The Genie has more
Expendable Cheats at CheatingDome.com.