All Systems

Random Select: Press up and start at the character select screen.

Stealth Select: At character select screen, press up, right, down, left, up.

Note: All of the next codes are done at the start/options screen.

Sound Test:  Press A, Y, B, X

Kool Stuff:  Press up, up, down, down, left, right, A, B, A

Kooler Stuff:  Press select, A, B, right, left, down, down, up, up

Scotts Stuff:  Press X, B, A, Y, up, left, down, right, down

Tournament Mode: At the main menu, highlight "Start", and hold BL and RUN.  While still holding these buttons, press Start.

Activate Robo-Smoke:  Turn on the system.  At the first screen, hold Back+A.  At the second screen, hold Foward+B.  At the third screen, press X+Y.  If the kode is done correctly, Smoke will walk out onto the next screen.  Now he is at your command.

Secrets:  Press B, A, Down, Left, A, Down, C, Right, Up, Down

Cheats:  Press A, C, Up, B, Up, B, A, Down

Killer Kodes:  Press C, Right, A, Left, A, Up, C, Right, A, Left, A, Up

Endurance Mode: At the main menu, highlight "Start Menu".  Hold A, B, and C, and press start.

Access Robo-Smoke:  At the MK3 logo, tap A, B, B, A, Down, A, B, B, A, Down, Up, Up.  From this point on, Smoke is at your control.

Playstation

Secret Cheats:  After the game loads for a bit, you'll see a cinema intro with Rayden.  As soon as this screen appears, press X, L1, L2, and press start.  You will hear a swooshing sound.  When the menu block appears with the word "Kombat" on it, press UP and you'll see a blue question mark.  Press any button to access this, and you'll get a Cheat Menu where you can access levels, Smoke, unlimited fatality time, and free play.

Secret Cheats:  To activate the kode above with more options, do the exact same, but instead enter this kode: X, Circle, Triangle, R1, R1, R2, R2, R1, R1.  You will hear Shao Kahn say,"You will never win".

Activate Robo-Smoke:  When the game is in the attract mode make a clockwise circle on the pad.  Then the game will ask you to enter the UKK.  Enter 0-1-0-6-9-6.  If the kode is done correctly Shao Kahn will say "Outstanding".  Then a message appears: "From this point on...Smoke is at your control".

PC

Enter these next kodes to start the game:
MK3 603015    Slow Motion
MK3 8000        Turbo Mode
MK3 12345      Tall Characters
MK3 54321      Miniature Characters
MK3 1111          Miniature Characters That Float
MK3 8888        Jumbo Characters
MK3 1995        Invisible Kombat
MK3 831          Characters Turn Invisible
MK3 9966       Mirror Mode
MK3 0666       Smoke Enabled
MK3 1000000 Shao Kahn and Motaro Enabled (only in 2 player mode)