Mortal Kombat

Cheat mode:
Type cathulu at the screen with the start game and options selections. Select the "Cheatmode" option that appears, then type rjc at the cheat menu. The cheat statistics screen will be displayed. Press [Space] to return to the selection menu.

Cheat mode (alternate):
Type abcdefghijklmnopqrstuabcdefghijklmnopqrstuabcdefghijklmnopqrstuabcdefghijklmnopqrstu at the screen with the start game and options selections

Disable blood:
Enable cheat mode, then type vampire at the cheat menu.

Fight against Reptile:
Kill your opponent with a double flawless match and a fatality on The Pit, after various objects pass over the moon.