With stats and levels that ridiculous it rather ceases to be a game. People will do stupid things that destroy other characters in a single round. Given the absurd amount of hp monsters will probably have, it's headed for a Wizard, Arcanist (the spell level penalty doesn't matter when you have that many levels ensuring 9th level spells anyway), or Mystic Theurge where you focus on Save or Die or Save or Lose spells really. Dazing Spell metamagic turns every damaging spell into save or lose, of course. You also have access to things like Time Stop to do extended spell preparation routines.
Really there's not a whole lot of optimization needed there to be ridiculous. I recommend Mystic Theurge Arcanist/Cleric with a large amount of Spell Synthesis feats and metamagic rods of quicken spell and persistent spell.