Kefka, but wasn't he in Final Fantasy III?
Wait, there's two different Final Fantasies II and III. The NES versions and the SNES versions, is that what you did there? I prefer to pretend the NES versions never existed.
So for me, it actually goes:
FF I (NES)
FF II (SNES)
FF III (SNES)
FF IV (Non-existant)
FF V (SNES)
FF VI (Non-existant)
and so on...