Samurai Shodown - Unlock Bonus Options: Play with any character and beat Story mode. Then at the Main menu go to Versus mode and highlight the 'Option' selection and hold L1 + L2 + R1 + R2 and press Start.
Samurai Shodown - 1-Play as Amakusa Shiro Tokisada: Play with any character and beat Story mode. Then 'Save' the game and at the 'Character' select screen go to Versus mode and highlight the '?' and hold L1 + L2 + R1 + R2 and press Start.
Unlock Kuroko and Mizuki: Press L1 + L2 + R1 + R2 at the 'Versus Character Select' screen and press the right arrow for Mizuki and the left one for Kuroko. Only one player can use these characters at a time.