Okay. Mystic Gohan kicked Buu's butt when it took Vegetio to even compare to Super Buu. Granted Gohan does get absorbed. But Goku could not even lay a killer combo on Buu. All damage not done by a fusion dance is by Gohan. Meant to be the main antagonist of the series, proved his worth when he defeated Cell. Also of which Goku could not defeat. But that's another subject. Gohan's full power is something he is ashamed of. Gohan defeated many who Goku couldn't. Raditz at the beginning to Cell in the End, Gohan displayed a higher power level than his fathers (Singular) highest power level. Succeeding SSJ 4 Goku.