I do believe the original Resident Evil is the first dual Gamecube disc.

I am waiting for mine to arrive in the mail(i took the slowest and thus cheapest shipping method). I am kicking the living hell out of Xenosaga right now. Jr. is dealing over 1600 per turn and sometimes as high as 4000 per turn.

Tales and Star Ocean sport a similar style battle system but lets face it....Star Ocean blows in comparision.