Anko - 15% mission completion for Orochimaru.
Asuma - 30% combined mission completion for Ino, Shikamaru, and Choji.
Baki - 30% combined mission completion for Gara, Temari, and Kankuro.
Bando - 20% mission completion for Kabuto.
Itachi - 30% combined mission completion for Kakashi, Asuma, and Kurenai.
Kabuto - Unlock all characters except for UNT Naruto, SS Sasuke, A Hinata, Bando, and Kagura.
Kagura - 30% combined mission completion for Kabuto, Bando, and Tsunade.
Kisame - 30% combined mission completion for Guy, Asuma, and Kurenai.
Komachi - Finish the Story Mode on Difficulty 2 or higher.
Kurenai - 30% combined mission completion for Hinata, Kiba, and Shino.
Orochimaru - 20% combined mission completion for Jiraiya and Tsunande.
Towa - Finish the Story Mode on Difficulty 2 or higher.
Yugao - 30% combined mission completion for Baki, Komachi, and Towa.