ruby and emerald were really easy. i have a materia combo that will kill them and i have only to touch the controler 8 times. the combo is counter comand paired with mime on ur armor. final attack paired with phionex. knights of the round paired with hp absorb and hp and mp pluses and w summon. enter the battle with ur 2 other chars dead. cast knights of the round twice with w-summon or do knights with a quandra'd bahamut zero(optional) then just sit back and relax. he'll hit u with ultima for about 5k damage then u hit him back for about A TON and absorb ur self back to full hp. rinse repeat
I WIN!!!!!!!!!!!!!!!!!!!!!!!!!!!!