Quote Originally Posted by Mr. Burns View Post
You can only find one, yes, but when it is mastered it gives birth to another. Master that and you have three. The number of materia you can have is limited only by the space allocated in the inventory*.

* Enemy Skill and Underwater cannot be mastered in the usual way and do not give birth to new materia.
I thought that didn't count with summon materia.

Boy, that's a good waste of months of your life right there.