Secret stage in Mortal Kombat 3 (Sega Genesis) 

Battle in air. Defeat Shao Kahn. When on the screen you will see the inscription You Are The MK3 Champion. At this point, press the [Start] button on the second joystick to turn on the two-player game mode. Choose any two fighters and start the game. You will fight in a secret battle zone where there is no floor. If you give your opponent an uppercut, you will be out of the game.