I'm an idit.

With flight he could fly at Kuja. Kuja flying on the Silver Dragon could cast various spells at him. He could dodge of course. But Flar Star surrounds him with different bolts of energy and has them collide goether, completey knocking him out of the air. He's not down yet though. He goes to get up, but using Deathguise to distract him, he gathers the souls of the Invincible and drops down to the ground. He let's the idiot attack him wildy. Using different forms of magic. As soon as he felt life slipping away, anger swelled inside him and BAM!! TRANCE! ULTIMA!!!! No one can survive Ultima.

Edit:

Raziel says: Kuja`s, no minions, no vehicles dammit. Pets are the exception. The Silver Dragon is Kuja's pet.