He actually succeeded in taking over the world for a while, and it took more hero's to bring him down then it did Sephiroth, plus, he's simply a much better and interesting villian.
Get LordRyugen in here, he knows more about Seph than me. Though I heard something about holding back a full blast from Holy, and beating up on AVALANCHE at the same time. HOLY people.
__________________ DarkCrawler is my hero... RESPECT LEONARD NIMOY!!!
sephiroth would win i mean Kefka is a cool and funny villan espcially with this crazy laugh but Sephiroth becomes a god and dispite all his magic Kefka would get tottaly trounsed
__________________
"Why do good and evil fight as they do? The more friends you have, the more birthday presents you get!"
right you are. we call sephiroth a god due to his sheer power but kefka is letterally a god. he can control all the magick and shape of the planet as he chooses.
__________________
Humans are afraid of the dark.
And yet… At the same time, we’re fascinated and bewitched by it.
Maybe that’s why humans drink the darkness that is coffee.
Well Dizzle ask and thou shalt recieve. Sephiroth at the height of his power held back the most powerful Weapon of the planet Holy. All the time maintaining a shield only the Sister Ray could penetrate, he also held it during all three fights when Aerith's prayer came into effect. Still I think Kefka stands above him in terms of power. Sephy'll give him a lot of trouble, but if they're both at their best...well Kefka takes the match.
For me personally, I actually lean more towards Sephiroth, simply because he has shown far greater abilities. Kefka has the Light of Judgement which is incredibly powerful, and he also has his final form of the six winged demi-god form.
However, Kefka is at his absolute peak in powers during the end of Final Fantasy VI while Sephiroth continues to only grow stronger, and although their is no actual "true canon" source available for the FFVI final battle conclusion with Kefka. However in FFVI Anthology, we are witnessed to Square's interpretation of Kefka's defeat and it was at the hands of a Alexander who was summoned to destroy Kefka.
This is the most likely scenario that I would take as canon, considering it was done by Square themselves, and so far it is the most recent and up to date Final Fantasy VI to this day. We do this as well with the Street Fighter storyline as well, until either it is refuted with a newer release of the game itself, or else refuted and changed by Square Enix themselves. However, until then, this is the most likely scenario imo.
Kefka was defeated by a summon of pure holy properties, yet Sephiroth was seen holding back Holy from the planet itself, which without a doubt in my mind would have surpassed even the being that destroyed Kefka.
It took an entire planet's lifestream+Holy to stop Sephiroth's summon from going into full effect, which would have allowed him to become a God. While Kefka was defeated by a bunch of mere mortals who simply summoned a Holy Entity to defeat Kefka. Not to mention, Kefka once dead...is dead period...while Sephiroth can return to become even more powerful then previously before.
Looking from it all, I'd chose Sephiroth over Kefka, even from an antagonist value, Sephiroth trounces Kefka, imo, Kefka is highly overrated, for how one-dimensional his character really was.