Quote Originally Posted by Sain Cai View Post
As said many times before, Omega Dungeon is the place to go. Not only for the Lvl 3 spheres, but also the sphere levels to go along to use them
I agree. However, if you do a fair amount of leveling before getting access to Omega, you will run into a few lv. 3 locks. Therefore, the best place to get lv. 3 key spheres pre-Omega is from Biran and Yenke.