@LosKnoggos:
Thats… ridiculous. Kefka hinted in the first one that Terra did bad stuff some time ago... But Cloud and Tidus and not Kain/Cecil? Really? bullshit.
Edit: ad shouldn't pre-mindfuck Cloud have not the Buster Sword, but a normal Soldier sword? Trying to nitpick here, since I really dislike the idea of him being chaos.
Well, that's my extrapolation, anyway.
We know based on the story for the original Dissidia that some people changed sides, don't we? So we know Jecht goes over to Chaos - consistent with FFX. It'd be sort of weird to have Tidus, whose primary hang-up in Dissidia is settling things with his old man, to be fighting it out with Jecht with Yuna around I guess.
Cloud was at times mentally controlled by Sephiroth, and we know that back when he was in SOLDIER, he looked up to him and followed him– didn't really seem to have an issue with anything Shinra was on about until Nibelheim. I can see it, I guess.
As far as Kain goes, we know from early trailers he betrays the warriors of Cosmos at some point, as he attacks Firion (ever the damsel in distress, aren't we?), which Lightning soon discovers.
but far as Cecil goes though idunnowhaddafuck.