This is a very old thread, I forgot all about this.
Anyway, the Yellow Trinity can be earned by beating the Collseum's Phil Cups, Pegasus Cups, and Hercules cups. Oh to get into the collseum, just go up to the rock and push against it by pushing the analog stcik towards it. It won't move, that's okay, then go talk to phil and he'll talk to you then. I think you got the rest.
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