It is the bad guy you face at the end of the floating continent before you get to the end where you meet kefka and Gestahl. He was called atma weapon in the snes version and in the advanced it was changed to Ultima Weapon.
It is the bad guy you face at the end of the floating continent before you get to the end where you meet kefka and Gestahl. He was called atma weapon in the snes version and in the advanced it was changed to Ultima Weapon.
Although in this case people are specifically referring to the sword you get in the sealed cave.
Perhaps you missed it? It's in a chest. In the lava room with the shifting bridges if I'm not mistaken.
Good thing that I like to explore every corner in the game, I got the weapon on my first playthrough.