Unlock 9 tailed fox Naruto:
To unlock 9 tailed fox naruto beat 1 player mode with every characher 2 times after you get Rock Lee.
Unlock Rock Lee:
To unlock Rock Lee beat story mode without having to continue.
Play as Unmasked Haku:
Highlight Haku in Character select and press X. When you fight your playing as Unmasked Haku.
(supplied by: narutofan666)