Well if I sub in Carbuncle for one of Rydia or Rinoa's ability slots I can keep Reflect up to deal with Death, yes?
In that case I wouldn't be worrying about her damage against Ultima as much as for the Mana Sphere. I would think it should save a couple ability uses for after the second phase.
If that still sin't worth it, though I could do a full mage PT too.
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