When you complete the following tasks the corresponding character will become unlocked for purchase. Kankuro, Kurena, Yugao, Itachi Kisame, Jiraiya, Tsunade, Temari, Asuma, Baki, and Anko are already available for purchase.
Unlock Hidan and Kakuzu:
Complete 30 of ALL Akatsuki member's missions.
Unlock Sai, Yamato, Sasuke, Orochimaru, and Kabuto:
Purchase ALL the other characters except for Hidan and Kakuzu.
Unlock Towa, Kagura, and Komachi:
Either have a saved game file from 'Naruto: Clash of Ninja Revolution 2' or purchase ALL the other characters.
Unlock Chiyo, Deidara, Shino, Hiruko, Sasori, Shikamaru, Kiba, Hinata, and Choji:
Complete Story mode.
Have at least 700 to 800 battles and purchase ALL other characters.
Unlock Anbu Kakashi:
Defeat Anbu Kakashi.