Play as the Student
While you are at the character select screen you can hold the L1 + R1 buttons and hit the X button to make your selection. Instead of your fighter you will be the fighter's student. This is indicated next to your name as you fight.
Play As Last Boss
Clear the tournament to unlock the character. To play the character hold L1, R1, L2, R2 and press X.
Unlock Training Characters
Clear every dojo on single player.
