Kefka as a playable character?

A Good Kefka Hack in a nutshell...
1. Have Terra and Kefka switch roles from heroine to villainess and villain to hero.
2. Replace Leo with one of the main characters, Locke, Edgar, Sabin...whoever.
3. Replace Leo's main storyline with Edgar or Locke or someone like that.
4. Come up with a story...get some inspiration, read some stories or watch some movies to let the creative juices flow. Why does Kefka want to save the world? What are the other character roles, is there a love story between party members? What relationships between the characters can you show? Who is the bad guy, what's his reason for messing the world up? Look for sprite sheets on the site for some other party members to replace the main roster.
5. Come up with some entertaining dialogue.
6. Change the abilities and weapons Kefka uses like Magic, Weapons among others.
7. Learn how to use the editors FF3usME and FF3se, they are your best friends. Look for tutorials for them on youtube and watch those for some guidance, you won't make a Kefka hack without them.