If you are at level 99 and you cant win there is something wrong, I was only at level 43 when I beat him. As soon as your 1st party dies and you switch in your 2nd one. Immediately cast Arise on your dead party so you can switch them back in if your 2nd party dies. You can target them by tapping L2. All you really need to do is make sure all your characters have a status of haste, bubble, and bravery. Cast Berserk on your Strongest Character. Then, have one character constantly healing, while the character with Berserk attacks, Your 3rd character can attack/support if needed. Also dont forget to use Dispel on the Esper.
You should equipp the character that has Berserk with a Katana, Katanas can hit multiple times in a single attack, also with the Speed boost that Haste and Berserk gives your character, they will be attacking at 3x the normal speed.
Xbox Live Gamertag = Keep It MovingCurrently Playing : Pokemon Pearl, Odin Sphere, Bioshock, Halo 3
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