How to beat Ultima Weapon:

1) Raise your stats for eternity

2) Raise them some more

3) Make sure you have Protect, Shell, Berserk and Flare or Holy at level 6 or higher

4) The higher level your cure and life spells, the better

5) Stop trying to make everyone good at everything. Have one black mage, one white mage, and two fighters

6) Make sure your fighters have weapon skill of at least 7

7) Stop giving your mages heavy armor and powerful weaopns, it just cripples 'em

8) Raise your stats some more

9) Buy lots of phoenix downs and elixirs (ethers are okay, don't bother with hi-potions though)

10) Before fighting him, get the stat bonuses from the 4 orbs surrounding Ultima


When it comes to the fight itself, cast Shell and Protect on everyone ASAP. Also make sure to Berserk your fighters right away. Do NOT cast Fire, Thunder, Blizzard or Scourge on Ultima Weapon! He's strong against ALL of those spells, and Flare/Holy have more attack power anyway. Keep hacking and nuking away and heal when necesarry. He's got some pretty powerful attacks up his sleeve. Don't be suprised if one or two party members get KO'd here. He's tough, but it's worth it. Give Ultima to your white mage and it oughtta work wonders. Seriously, in my game it did more damage than Flare (which is stronger than Holy) when it was still 2 levels behind!