Guys, I've heard that there's a better weapon than those Celestial Weapons, i.e Tidus's Excalibur. Can someone help me on how to customize those weapons? And what items do i need to get the Break DAmage limit, Break HP limit and Break MP limit?

ALso where can i get some of the lock sphere and Att. spheres? I can't seem to find the STR sphere... where can i got those kinda spheres?