Fight as Akuma At the Street Fighter 3: Second Impact character selection screen, highlight Sean and press Up.
Fight as Gill Complete Street Fighter 3 or Street Fighter 3: Second Impact on any difficulty setting. Then at the character selection screen, highlight Sean and press Up, Up.
Fight as Yang At the Street Fighter 3 character selection screen, highlight Yun and press any Kick button.
More Street Fighter 3 Double Impact cheats at: Cheat Masters
Lords of Legend RPG 
