Heh, trust me, after facing the other Big Bosses in the game, this guy is a snap to beat.
What I suggest you do when fighting him is activate your "Aero/Aerora/Aeroga" magic and the battle should go by quickly. When he does his "Final Darkness!" attack, quickly race away and keep on going until the attack ends. Then go back to kicking his tail and he should be defeated in no time.
vvv credit to .Impact.
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