Hold Square + Up immediately before the race begins.
Begin game play in grand prix mode and continue until requested to choose
between Chocobo and Behemoth class. Finish in first place in every stage to
get the crown for that stage and class. Bahumut class will be unlocked after
collecting all crowns for both classes (and the Final Fantasy 8 track).
Collect all crowns in Bahamut class (including the Final Fantasy 8 track) to
unlock the mirror mode selection on the options screen.
A bonus character will be unlocked each time story mode is successfully
completed. Highlight Squall at the character selection screen and press the
Times completed Character Code
3 Cid L1
4 Mumba (Final Fantasy 8) L2
5 Cloud (Final Fantasy 7) R1
6 Cactuar/Cactrot R2
7 Aya (Parasite Eve) L1 + L2
8 SD-style Chocobo R1 + R2
9 IbenSuper airship L1 + R1
10 Jack L2 + R2