Pylis on 13 October 2009
I'm surprised this hasn't been said yet:
Combine "Knights of the Round" with "HP Steal" materia.
Combine a max level "Counter" materia with "Mime" materia.
At the start of either Ultimate Weapon battle, using the character equipped with the materia combo listed above, cast Knights of the Round. Now, do nothing.
Every time your character with the materia combos above is attacked, he or she will counter with Knights of the Round at no MP cost, leeching back 9999 health. You can literally walk away from the battle and come back a few minutes later to the victory screen.
