I need help on Kingdom Hearts 2 please?

I'm stuck on the Underworld place on the Colosseum and there was a scene where this locked up place opened and then there was a tournament and I beat the Pain and Panic Cup and now I don't know what to do. I am not REALLY stuck, but I don't wanna waste my time on it looking for what to do, so if you can just give me clues, then thanks. Don't tell me to go on www.gamefaqs.com because I don't wanna go on it. I don't know why but I don't want to for some reason. Haha... ha. Well, just tell me! It's faster!