dragontigerviper

goku had the spiret bomb but not enough energy to use it against Buu. kinda like having a loaded gun by no fingers.
Buu was strong enough he could use his strength to hold back the force of the bomb. the genkia-dama, while powerful, is still just energy and can be deflected if the person is strong enough to do so. it's only quirk is that it can not directly kill one whom has a pure soul.
and as for that comment about Vegeta dodging, don't blame Krillen, it was Yajerobi that directed Vegeta's attention by shouting "Just Throw it already!"

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