I've honestly always enjoyed Zenos as a character. He's such a picture perfect image of a classy FF villain with his own distinct story and personality. Moreover, as the only one who has managed to single handedly hand our ass to us multiple times, I feel that there are few better opponents fit to be the big bad, or at least play a role in the grand finale. In terms of spirit and power, he is our equal and opposite. He openly calls us out for not really being part of this world, for instead living for the intense life or death moments, for the emotional tragedies and the ecstatic returns, and claims to share that reason for living as well. It's almost like a 4th wall break of sorts. I have no clue what they intend to do with Zenos but I have no issue with him playing a major role again in the MSQ. He's probably the only person we as the WoL would actually consider a serious threat we might not have the power to defeat, and I love how they've been adding onto that by having Zenos literally return from the dead of his own volition (as far as we know) and when he gets his body back suddenly having Ascian powers out of nowhere and then being able to *remember* events we only saw through the good grace of Emet-Selch. He's becoming almost a Nemesis-esque character and I'm eager to see the direction his story goes, though I suspect that he may not be our true endgame villain. To me Fandaniel seems too insane to be totally wacko and unhinged, I feel he is likely the complicated, tragic center of this entire narrative. As for how, we can only guess, but I don't believe he is a random subordinate bad guy whom is only here to help the villain get what he wants.