Hidden Fighters
Ball - Finish the game with all characters on any difficulty setting.
Big Zam - Finish the game on the easy difficulty setting.
Gundam - Finish the game with all Suits on the normal or hard difficulty setting.
Hydra G - Finish the game on the hard difficulty setting with out losing.
Psycho Mk III - Finish the game on the hard difficulty setting.
V Gundam - Finish the game with all Suits on the hard difficulty setting.
Zeue Ziel - Finish the game on the normal difficulty setting.
Unlock Char's Zaku
In the first screen, where you select story game, vs game, memory card and options, press "down, left, up, right, square, triangle, circle. If you did it right, it will make a sound and you can play with char's red zaku, in vs mode.