Below a list of some unlockable characters in this game:

Effect - Code

Black Assh - Successfully complete Arcade Mode eight times.
Dearka's Zaku - Successfully complete Arcade Mode six times.
G Route - Successfully complete Arcade Mode once.
Gaia Gundam: Andrew Waltfeld Custom - Beat Arcade Mode nine times.
Gells-Ghe - Successfully complete Arcade Mode four times.
H Route - Successfully complete Arcade Mode twice.
Heine's Zaku - Successfully complete Arcade Mode three times.
I Route - Successfully complete Arcade Mode eleven times.
Stargazer - Successfully complete Arcade Mode ten times.
Yzak's Gouf - Successfully complete Arcade Mode five times.
Zamza-Zah - Successfully complete Arcade Mode seven times.