I was able to survive that because Gaia subbed in after the first death, allowing me to recover HP during the normal phase of the final boss, and heavily mitigate the overdrives. Otherwise, any debuffs missing would've probably been lethal. A Water team with Gaia is literally the most tanky group you can have with elemental disadvantage against the final boss. Not only can she 100% mitigate the boss's overdrives 50% of the time, she can also 60% mitigate the others due to the Thunder resistance buff on her damage cut, and this applies to normal attacks too. Then add Blind, Charm, Combo attack down, and her healing, and the build's tankiness is really impressive. Though an untimely Charm proc can instantly end you, of course.