Firstly, I am glad to hear that you have recovered and that your life is faring well again, as I was also worried about you when I heard about your seizure. I know how rotten life can be also when ill health follows or coincides with other stresses from work, school or family; good on you for refusing to leave your story unfinished. I have managed to keep up with it in spite of my usual academic pressures (although this is my last term of coursework and it will finish at the month’s end); reading the story is a pleasant break from other things these days.
As for Vegeta, I am not sure how useful any advice that I offer may be, since I know scarcely anything about Dragonball Z. In any case, one chief advantage that the RPGC party have over Vegeta is numbers; as powerful as he may be, if they spread out, he may not be able to target all of them when attacking, and Vegeta will expose flanks. Even if he can sense things all around him, he may not be able to attack as efficiently if there are multiple targets around him, which may frustrate him. Of course, the party have little time to contrive their strategy.
Perhaps, too, they might provoke Vegeta to use up a lot of his power by feigning weakness and letting Vegeta try a blitzkrieg strategy, but suddenly counterattacking from all sides when he is tiring but confident that he has won. Status ailments, as nicely already suggested, would certain help here, especially if one were to cast many on him at once, as a marlboro’s Bad Breath does. Resistant as he might be to status ailments, it would not strike me that he would be immune to all unless it were specifically evidenced. Another option, if they will work, are illusions; again, I cannot conceive that Vegeta is immune to them unless it is so stated somewhere, for strong and well-crafted illusions can deceive even gods. Xero undoubtedly has a strong ability in arcane magic, so I should expect that he knows at least some illusion spells. An idea here would be to have Vegeta use up his powers on a vast multitude of fake targets all around him, or frustrate him with an illusion of something or someone that he loathes (this Goku, perhaps?)
A final and rather risky strategy would be energy drain (either through a spell or by summoning a creature with energy-draining attacks), although this assumes that one can successfully strike Vegeta. Since Vegeta has so much energy, he would probably attract a negative-energy creature easily if one were summoned. Negative-energy creatures, however, tend to be evil and undead (but not always), so there are always potentially grievous contingencies to hand.
Regardless, hopefully that may stir up at least a few ideas. I am somewhat relieved in any case that my character is not in this battle!
