At the VS screen, press the following buttons to activate the corresponding Kombat Kode:

Blocks disabled: Press BL(2)
Dark Kombat: Press LP(6), BL(8), LK(8)
Fight Galaga: Press LP(6), BL(4), LK(2)
Fight Motaro: Press LP(9), BL(6), LK(9)
Fight Noob Saibot: Press LP(7), BL(6), LK(9)
Fight Shao Kahn: Press BL(3), LK(3)
Fight Smoke: Press LP(2), LK(5)
Infinite run: Press LP(4), BL(6), LK(6)
No life bars: Press LP(9), BL(8), LK(7)
Player one has 1/4 energy: Press LP(7), LK(4)
Play as Smoke: Press HP(1), BL(9), HK(2)
Psycho Kombat: Press LP(9), BL(8), LK(5)
Randper Kombat: Press LP(4), BL(6)
Throws disabled: Press LP