MORTAL KOMBAT 4
At the options menu, highlight CONTINUES and hold run and block. Soon, a cheat menu will appear.
After you access the cheat menu, select the "hidden" option at the bottom of the screen. Then go up two and over one to Reiko. Press and hold RUN and BLOCK to select him, and hold it until the match starts to become Noob Saibot.
After selecting the "hidden" option, go up three and over one to Shinnok. Press and hold RUN and BLOCK to select him, and hold it until the match starts to become Goro.
To access hidden uniforms, put your cursor over the character you wish to fight with. Hold down start and press A. The picture of the character will flip. Do this once to gain an original costume set (for characters that were in MK, MK2, or MK3). Do this twice to get a new costume or a new weapon to use.