K-1: The Arena Fighters Cheats

Alternate costumes:
In the title prompt, hold L1 + R1. You will hear three beeps if you have entered the code correctly. Push Start to pick alternate character costumes for Musashi, Andy Hug, and Sam Greco.

Unlock Master Ishii:
Pick team battle mode. In the character selection prompt, push Up(2), Down(2), Left, Right, Left, Right, Start. Master Ishii will be selectable to the right of the regular characters.

Set strength level:
Press Start to pause your game and push L2, R1, L1, R1, L2, R1. Use the D-pad on either controller to change the flashing numbers on either side of the screen to any value between one and nine for the corresponding player.

Unlimited energy:
Rapidly push Up, Right, Down, Left, Up, Right, Down, Left, Select when the phrase "Push Start" begins to flash on the title screen. The sound of an explosion will confirm correct code entry. REMEMBER: This code affects both players.

View ending sequence:
On both controllers, hold L1 + L2 + Triangle + Circle + Left when turning the power on the PlayStation. Continue to hold all buttons until demo mode starts to view the ending sequence and credits.