Gameplay wise Tidus and Seph are reduced to little more than Hop Step and Shadow Flare respectively. You can blame assists for that. Sort of the same with Zidane and Swift Attack -> Meo Twister, but he has plenty of options other than that and plays swiftly and nimble. Similar to Tidus, except Tidus' mobility comes out through his dodge moves which kinda force Hop Step to be his only offensive option, while for the rest he has to turtle somewhat. Kefka is fun to play as, and really annoying to play against thanks to WW Firaga and that really weird Havoc Wing hitbox.
Of course, Vaan is one of the most fun characters to play and went out first, even before Feral Chaos, the embodiment of the devastation to the Dissidia 012 metagame. So the game bias argument does have some ground to it.
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SomeC - sheer explosives since meeting that crazy hobo.
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