Majuub

Goku stated that someone stronger than him would come to face Fat Buu. He later says with confidence that he could have beaten Fat Buu. Maybe SSJ Gotenks was dead even with Fat Buu or maybe he was stronger. Piccolo was impressed at the power Gotenks displayed after his training, it means Gotenks powered-up quite a bit, maybe a this point he was dead even with Goku or much stronger. I don't think even with that training he would have been able to take on Janemba, I don't think his rather short training gave him enough time to dominate Goku as easily as Janemba did. For this one, I'll have to go with Janemba, I think he his stronger by quite a bit.

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