Hm...

Xande: Barely exists or is discussed, so much for the great "first villain with a real explanation why he's evil."

FFVII: Sephiroth's threat is built up perfectly and Nibelheim Flashback is a highlight of the whole game. Sadly, his change in personality and motivation makes no real sense and is never explained.

FFVIII: Ultimecia has no character. She is the Zemus of FFVII. All attempts to read more into her personality is a laughable endeavor because her "motives" are based on Xande-like "one line here, another line here" and nothing more. She's just evil and stupid.

FFIX:Kuja is possibly the best FF villain ever. Sensible backstory, good characterization, memorable design. He also never truly lost as he killed the party in the final battle. Gotta give him points for that.

FFXII: I'm not sure who the main villain is here. Vayne? Venat? I preferred Dr. Cid, anyway. Great voice-actor, great dynamic with his son.

FFXIII: Barthandelus really had potential. The fal'Cie being the real slaves is an interesting plot point. It's just that no character besides the playable ones are allowed any real screentime or focus. He has a good voice and was a wonderful troll, though.

FFXIII-2: I smurfing love Caius. Great motivation, great voice, great music. My main complaints would be the fact he's actually not in the game enough and his sword looks dumb. It shouldn't even be a sword, just some sort of "arm-weapon" ya know? But yes, I love his lore and understand why he is doing what he's doing all too well.