I never played it on GameCube. That battle... I was stuck on for about 2 months! only one that ever took me so long! Anyway... don't use a lot of sleights unless you have a lot of item cards... they'll eat up your deck... use 7 or above #d cure cards to avoid having to use them is sleights! Have lots of 0's! 0's and 9's! Break all of the Dark Aura attacks... the one when he warps around the field then makes it so Sora is confused, and don't let him get a combo on you... it paralyzes Sora...
It will probably take you a while... It really is one of the more difficult battles. I found it harder than the final boss...