If I tell you more about my magic you have to tell me more about your magic.

[He's laughing. Seriously though, he's pretty damn curious.]

My magic comes from those rocks and they're called materia. They're made up on the lifeforce of the earth so they're literally contained energy sources. Get a fire one, you can cast fire. Get a thunder one, you can zap shit. That's pretty much the basics of it. They usually have to be slotted into weapons and armour to help with aim and the strength of the spells. Plus it's easier to carry them around.