Veemon has many forms at his disposal once. Veemon has his legendary Magnamon form and with it he’s got some pretty intense hand to hand skills. Mewtwo’s extremely fast and he could maybe hold his own for a while, but the more that Veemon digivolves, the less chance that Mewtwo will have of pulling out a win. Mewtwo won’t be able to pull out a win in the end. Veemon wins.
Update- Mewtwo’s Mega Form has turned the tides. Mewtwo wins.
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Veemon can digivolve to imperialdramon paladin mode who is much more powerful than omnimon x who can create and destroy universes.
I’d say that this is pretty debatable. Omnimon X would likely crush Imperialdramon Paladin Mode if they fought. At least, I would say so, but it would be a fun battle of powerful opponents. Omnimon is just one of the original Mega level Digimon and his feats are still impressive to this day
mewtwo wins easy
Mewtwo definitely has the skills for it