This guy has to be the coolest villain of the series. He was the first of Emperor
Gestahl's
Magitek Knights, followed by
General Leo and
Celes. The process of magic-infusion had been just newly rediscovered, and seeing as he was the first to give it a run there were some complications. He came out much more powerful than either Celes or Leo, but also became quite
psychotic and a little
cowardly.
Gestahl wasn't one to waste a valuable tool, unreliable though Kefka was. While Celes and Leo were out conquering the world for Vector, Kefka was left mostly to himself. He used his time to experiment on Terra, and only ventured away from the capital of the Empire to track her down when she disappeared. He was unable to regain her and she joined The Returners (the standard rebel goup). Angered at the loss, he became active in the war effort. To make a longer story shorter, his crowning achievement during this time is committing genocide on Doma by poisoning their water supply.
When Gestahl captures the floating continent and becomes the ruler of the world, Kefka murders Leo and razes Thamasa, thus becoming the emperor's right-hand man. Then, right at his moment of triumph on the remnants of the Returners, Gestahl is betrayed by Kefka, who takes control of the Goddess statues and blasts him off the continent. Now in total control, Kefka sets about destroying everything.
A year later, the world is a wasteland. With that business done with, Kefka is bored. All he can do is sit around sulking, shooting off the occasional ray of flaming death, and wait until someone finally takes him down.
The thing about him is, he's utterly insane. Unpredictable, random. He's got no boundaries. Zemus wanted revenge, Sephiroth just wanted to get a clue (it was his methods that were the problem). Chaos was literally a glorified Garland. The Cloud of Darkness was just a cloud, and Exdeath was just a tree. The Parmekian Emperor of Final Fantasy II might have rivalled Kefka in badassery, but we never really got a chance to know him. Kefka is the Hitler of the Final Fantasy series. His goals are so arbitrary! He might be genius (although that's unlikely), but he's so unstable that under no circumstances should a guy like him have control over anything.
I can see that I'm really starting to drive this into the ground, so I'll stop now with a few Kefka quotes: