Who/what villainous organization from the Final Fantasy series is your favorite? Main series or side series count (like the Tactics or Crystal Chronicles series). Mine would have to be Sephiroth with Kefka coming in as a close second. Sephiroth because of his connection with Cloud and Kefka because he's just nuts. 

Without a doubt, Sin from Final Fantasy X.
Oh, Final Fantasy, you and your habit for making every main baddy near-immortal.

Mine is a tie between Kefka and Sephiroth.  Both are almost god-like in terms of abilities and both are some of my favorite villains in any game. Kefka is insane and colorful, while Sephiroth is cool and awesome.  By the way, I'm kind of getting tired of FF fans arguing about which is the better villain, I just think that it is pointless to arguing about something like that.

I don't really know why, but I just really like Kefka. I guess 'cause he reminds me of The Joker from Batman? I just love his character, especially when he taunts Squall in Dissidia. xD

I would say sephiroth he has lot of attacks like gale horse shadow flare nova final move the heartless angel wall even basic sephiroth happens to be unquestioned final boss is hardest major compare by the villians I have fought of chaos emperor zeromus exdeath  kefka ultmecia and koja.

Well, in my opinion, the best Final Fantasy boss is Kefka, but since you're asking for our favorite. My favorite is Kuja from Final Fantasy 9. He's a much more complex and interesting character than some of the other villains. That's not to say the others aren't interesting. I just find Kuja more interesting than the others.

Sephiroth! He's just completely awesome to me. I liked him in FF7 but liked him even more when Kingdom Hearts came out.

Oh geez, most definitely Sephiroth! Come on now, the baddest of the bad - he's a ruthless "fallen angel" that loves despair. He is one master swordsman, and he just looks cool I should say. 

Genesis is a guy that you don't really know much about. His appearance in FF VII Crisis Core was a bit short, but if he were to have been a part of Dissidia, or much less stay alive, he would have been a really cool villain.

I'd say Sephiroth just because I loved FFVII and he was awesome.

Honestly, I can't pick any single villain as a favorite, although I can go for a favorite with each generation.

8-bit: Lich. Blame the fact that I'm a huge D&D geek, but it's just plain awesome to see an undead piece of work that's strong enough to go toe-to-toe with other crazy-powerful fiends.

16-bit: It's not a favorite singular villain in this one so much as it is a group, and for that I adore the Four Fiends of the Elements from Final Fantasy IV. One's a giant zombie with no self-esteem, one's a turtle-man whose head resembles a phallus, another is a lesbian who likes to get into hairplay, and the last one's both a streaker and, somewhat paradoxically, a gentleman, at the same time. There's just so much potential with these characters that I'm surprised the boards on Fanfiction.net aren't overflowing with stories about them.

Proof: http://www.youtube.com/watch?v=C8vz186pjY0

32-bit: It's a hard one for me, but I think this one goes to Delita from Tactics. Such a self-righteous bastard, one who manages to turn the entire nation upside-down and end up being its king. An apparently just (albeit very lonely) one, but still. 

After that, I must say that I've rather lost interest in the series, sadly. I might pick it back up later, but I just can't get into anything past IX.

This is a tough decision. Rubicant, Kefka, Kuja would make the final cut for sure. Might be forgetting somebody... hmm.

I have to say, I would likely lean to Sin from FFX.

Mostly because unlike the other "big bad", Sin actually has a story worth caring about. A villain isn't born, they are made. And Sin was made just right for the setting it was in.

Honorable mention has to go to Ultimecia from Final Fantasy VIII, and Kefka from Final Fantasy VI.

Tempted to side with Kefka, but I'm picking Gilgamesh!

His fight music, his humorous dialogue, and the very last battle that he shows up in.
I have a soft spot for FFV.

...Lowlifes. ...Shameless filthy wretches. How you celebrate my ascension with such joy. Hailing the very one whom you have condemned for generations. Have you no shame? What happened to the evil, ruthless sorceress from your fantasies? The cold-blooded tyrant that slaughtered countless men and destroyed many nations. Where is she now? She stands before your very eyes to become your new ruler...

The bosses that keep showing up are always fun for me.  I liked Golbez through that edition of Final Fantasy.  My favorite villain is Kefka without a doubt.  He was portrayed wonderfully throughout the game, making soldiers shake sand out of his boots and blasting towns and villages with his laser beam.  Awesome stuff and he was made to be hated.

The most interesting boss and the one that sticks in my mind is the phanton train from Final Fantasy VI.  You run the gauntlet with ghosts and other enemies and finally deal with the train itself.  The battle, which includes acid rain, is cool.  The music while one the train is deep and forboding, and the cut scene after when the train decides to let you off (so you aren't delivered to the land of the dead) is heart-breaking for the characters.  Great scene, great fight, great moment in a near-perfect game.

Kefka's pretty awesome, but I'd have to say my favorite is Sin from FFX. It's beautiful, powerful and challenging, and is just pretty awesome overall. Braska's Final Aeon was an awesome "final" boss as well.

I would say that Sephiroth is the best one out there. I mean, I am not the biggest final fantasy player, but I have played most of the games, and I love FF7, so I would have to go with him.

Kefka no doubt about that, he is the most meanest, evilest psychopath I have ever seen in final fantasy history, I love that guy. <3