Successfully complete the indicated task to unlock the corresponding character:

Algol: Successfully complete Story mode with a character that fights Algol as 
the final Boss (Mitsurugi, Taki, etc.). 
Amy: Purchase her in the Character Creation for 4,000 gold. 
Angol Fear: Defeat her in Story mode. 
Ashlotte: Defeat her in Story mode. 
Cervantes: Purchase him in the Character Creation for 4,000 gold. 
Hong Yun-seong: Purchase him in the Character Creation for 4,000 gold. 
Kamikirimusi: Defeat her in Story mode. 
Scheherazade: Defeat her in Story mode. 
Shura: Defeat her in Story mode. 
The Apprentice: Successfully complete Arcade mode with Yoda.