It's a double post, I'm sure someone will edit it out soon...
The emperor in the FC version had 2/8 action slots filled with physical attacks, meaning he'd attack roughly 1/4 of the time. As far as just using magic, it depends. He's resistant to all 8 elements, absorbs dimension and death spells, and no obvious weaknesses. This means unless you're casting non-elemental spells (flare, holy and ultima) you're not going to do much damage.
Racially he is an air being and an earth being. I can't remember right off the bat if that means he's weak to both air and earth, or resistant to both.
Physically, he can only dodge one attack, so you'll do almost full damage. His magic defense is 16.
Judge for yourself what your tactics should be.
