When you have collected ALL 100 souls of the Tenchu Army you will recieve infinite Dragon Warrior power even if your Chi bar is not full.
Secret Codes
Enter in Cheat Menu:
4x Damage Multiplier - Up, Down Up, Right, Left
Big Head Mode For Story Mode - Down, Up, Left, Right, Right
Dragon warrior Outfigt for Multiplayer- Left, down , right, left , Up
Infinite Chi - Down, Right, Left, Up, Down
Invulnerability - Down, Right, Left, Up, Down
Unlock all Multiplayer Characters - Left, Down, Left, Right, Down