Mark of Kri, The Cheats

Finish all challenges in a level to unlock a
arena for that level

Flip through the pages of the instruction booklet from the back to the front. There is an animation of Rau performing a stealth kill in the lower right corner.
Game Shark Codes
Master Code (Must Be On) 0E3C7DF2 1853E59EEEA5CF26 BCDF4372
Infinite Health DEA13BC6 BCA99B84
Infinite Arrows DE86BA5E BF899B8BDE86BA5A BCA99B83
Frozen AI DE82ADAE BF899B8BDE82ADAA BCA99B83
All Challenges Complete DEA16E2A BCA99B84DEA16E3E BCA99B84DEA16EC2 BCA99B84DEA16ED6 BCA99B84DEA16EDA BCA99B84
Turbo Mode DEA13E26 FC75674DDEA13E22 FE4C728DDEA13E36 FE619CE8
Press Select + R1 to Walk Through Walls 01EE1544 BCA99281DE85CF06 BF899B8B01EE1544 BCA99281DE85CF02 BCA99B83
Press Select + R2 For Walk Through Walls Off 01EE1544 BCA99881DE85CF06 E3669A4301EE1544 BCA99881DE85CF02 BB5B9BA3

Get full health:
At the start screen enter the following combo... X, X, X, X, Square, Square, Square, Square, Circle, Circle, Circle, Circle
Get unlimited arrows:
At the start screen enter the following combo... X, Circle, Square, Square, X, Square, Circle, Circle, X, Square, Square, X
Get stronger opponents:
At the start screen enter the following combo... X, Circle, Square, Square, X, Square, Circle, Circle, X, Circle, Circle, X
Get weaker opponents:
At the start screen enter the following combo... X, Circle, Circle, Square, X, Square, Square, Circle

Successfully complete the arenas by completing all challenges for both time attack and body count to unlock extra costumes and art.

Finish the Body Count & time Attack in each arena to unlock these