Beat all D-Ranked missions for curse mark Sasuke. Beat all b-ranked for Kyuubi Naruto (Nine tails). Also additional blows are the slow-motion moves you perfrom. There are several ways to do them.

1)Hit your oppenent with (up+O)repeatedly then press x 3 times (when thet're in the air), then up and o again.
2)Use grapple(opposite direction of enemy plus O) then point analog stick towards their direction with O
Do this the number of times they specify