Pause during a game, and press X + Y. The cleared pause screen gives you a full scree view of the spinning slow motion effect.
Pause during a game, then hold L + R and press A, B, A, B.
Pause during a game, then hold L + R and press B, A, B, A.
Pause during a game, then hold L + R and press Up, Down, Right, Left, A, Y, B, X, X + Start to play as a character that is part Kurt, Max, and Doctor Hawkins.
From the Main Menu, hold L + R and press X (x2), Y, X.
While playing as Max, hold R and press Up (x4).
While playing as Doctor Hawkins, press L + R + Left + A.
If you insert the game disc into a CD player, you should be able to play track two and higher to hear music from the game. The Dreamcast acts as an audio player if you start the system without the game disc, and then insert the disc afterward.
Find .JPG images, .WAV sounds, and .MP3 blooper tracks from the game in the "mdk2" directory. Just use a PC compatible CD-ROM drive.