Go to the main menu, hold the [Crtl] key and type in

 SKIDMARX

 Now two additional menus open up, which let you select a level
 and let's You tune your character. Additionally you can type in

 CREATURES

 to view all creatures' animations (You will have to type SKIDMARX
 first)

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 To get the biggest splatter party ever, activate the the cheat menu
 with [Crtl] and SKIDMARX and start the game. Pause the game with
 [Esc] and hold [Esc] and type in SKIDMAR. Now check what happens.