Goku was kind of even with Fat Buu I think but he says he wasn't being serious because he wanted Gotenks to beat him or something and he had a time limit on him or something? Obviously hugely outclassed by every Super Buu variation and Kid Buu took he and Vegeta to the limit and required a ton of outside assistance to beat. And GT is non-canon...ish? Been a while since I've payed attention to Dragonball stuff.
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We clasped our hands, our hands in praise of a conquerors right to tyranny