Well, this is open and close.

With minions:
Using Deathguise, Black Mege Type C, and those weird monsters Kuja makes from the Mist, he can set them all on Lioyd. From what I've heard, he's got a sword. No real magic or defenses. So he would be overwhelmed by the huge numbers of Kuja's puppets.

Without minions:
Well he could avoid Lioyd by flying around on his faithful Silver Dragon. From afar he could cast Flare, Holy, Meteor and eventually Flare Star. How could the dude with the sword defend himself? He couldn't. Eventually he'd die. Since he can't fight back he could run, but not for long...