Nightmare Creatures 2 cheats and cheat codes for Dreamcast

Select any stage:
Highlight the "Options" at the new game screen and press the following 
button combinations:
Hold B for 3 seconds, after press Y, A, X, B. 
Hold X for 1 second, after press B.

Cheat menu:
Pause the gameplay then press the following button combinations:
Hold L + R and press left, B, X, left, B, X, left, B, X, A, and X.

Watch Kalisto introduction:
If you insert your game disc into a PC CD-ROM drive, you can watch
the Kalisto introduction with any movie player.

Secret images:
If you insert your game disc into a PC CD-ROM drive, you will find 
lots of images from the game.

Full pause screen                                                 
Press X + Y, while paused the gameplay.

Screensaver:
Remain idle a for a few minutes.