Cheats Menu:-  At the trademark screen (after the one that says "Prepare For Kombat"), press these buttons in the following order: C, R, A, Z, Y, C, Y, R, A, X. You should hear a laugh. Then, at the UMK3 logo that is spinning over the options, press Up. A "?" box will appear. Press any button, and you will enter a "Cheats" menu with free play, unlimited fatality time, one round matches, and access hidden characters.

Play as Human Smoke:-  To play as Smoke in his human form, pick the Cyber-Smoke at the fighter-select screen. For Player One: Press and hold Left, High Punch, Block, High Kick, and Run simultaneously until the match starts. 

For Player Two: Press and hold Right, High Punch, Block, High Kick, and Run simultaneously until the match starts. When the fight begins, Cyber-Smoke explodes into human Smoke.

Enter the codes to play as the hidden characters at the "Enter an Ultimate Kombat Kode" screen. To get to this screen, start a game against the computer, lose, and do not continue. A screen appears asking you to enter a code. The following codes are entered on one controller.

Play as Classic Sub-Zero:-  Press X seven times, Y six times, A five times, and B two times.

Play as Ermac:-  Press X nine times, Y six times, Z four times, A two times, B four times.

Play as Mileena:-  Press X seven times, A seven times, B two times, and C three times.

Freeplay Mode:-  At the screen that says "There is No Knowledge that is not Power," press Up, Up, Right, Right, Left, Left, Down, Down very quickly. A voice says "excellent." Now the game is in free play mode and you have unlimited continues.

Kombat Kodes:-  Enter the following Kombat Kodes after selecting your fighters for a two player match at the "VS" screen. 

Button Presses are as follows:

Player One (on Controller One):
Slot 1 ´ Button A; Slot 2 ´ Button Y; Slot 3 ´ Button C
Player Two (on Controller Two):
Slot 4 ´ Button A; Slot 5 ´ Button Y; Slot 6 ´ Button C
(For example, for the Kombat Kode, "Blocking Disabled," Player One and
Player Two should press Y twice).
Special Abilities:
Blocking Disabled: 0 2 0 0 2 0
Fast Uppercut Recovery: 7 8 8 3 2 2
Hold Flippers During Casino Run: 9 8 7 6 6 6
Kombat Zone Kodes:
Balcony: 8 8 0 2 2 0
Bell Tower: 0 9 1 1 9 0
Blue Portal: 9 3 3 9 3 3
Bridge: 0 7 7 0 2 2
Graveyard: 6 6 6 3 3 3
Jade's Desert: 3 3 0 0 3 3
Kahn's Kave: 0 0 4 7 0 0
Kombat Temple: 6 0 0 4 0 0
Noob's Dorfen: 0 5 0 0 5 0
Pit III: 8 2 0 0 2 8
River Kombat: 0 0 2 0 0 3
Rooftop: 3 4 3 3 4 3
Scorpion's Lair: 6 6 6 4 4 4
Soul Chamber: 1 2 3 9 0 1
Street: 0 7 9 0 3 5
Subway: 8 8 0 8 8 0
Other Kodes:
"No Fear" Message: 2 8 2 2 8 2
No Powerbars: 9 8 7 1 2 3
Player One 1/2 Energy: 0 3 3 0 0 0
Player Two 1/2 Energy: 0 0 0 0 3 3
Player One 1/4 Energy: 7 0 7 0 0 0
Player Two 1/4 Energy: 0 0 0 7 0 7
Psycho Kombat: 9 8 5 1 2 5
Quasi-Randper Kombat: 4 4 4 4 4 4 or 4 6 0 4 6 0
"Rain Can be Found in the Graveyard:" 7 1 7 3 1 3
"See Mortal Kombat The Live Tour!" 5 5 0 5 5 0
Silent Kombat: 3 0 0 3 0 0
"Skunky! ´ E.F." 1 2 2 2 2 1
There is No Knowledge Without Power: 1 2 3 9 2 6
Throwing Disabled: 0 2 0 0 2 0
Throwing Encouraged: 0 1 0 0 1 0
Unikorn Referri: Sans Power: 0 4 4 4 4 0
Unlimited Run: 4 6 6 4 6 6
Version Number: 9 9 9 9 9 9
"Whatcha Gun Do? ´ E.B." 0 0 4 4 0 0
Winner of First Round Battles Motaro: 9 6 9 1 4 1
Winner of First Round Battles Noob Saibot: 7 6 9 3 4 2
Winner of First Round Battles Smoke: 2 0 5 2 0 5
Winner of Round Battles Shao Kahn: 0 3 3 5 6 4
You Are Entering the Land of Rellim: 6 4 2 4 6 8