[Ironhawk]

I'm just starting to get into the game and I've noticed something odd. In the labs I see the spell Flare and it is level 2 (or 3?) in Evocation. I have not researched it. Yet my priest, who has level 3 in fire magic is already casting Flare when I send him into combat. Clearly my original assumption that you need to research a spell in order to cast it does not seem to be holding true.

So, I find myself asking: what is the relationship b/w the magic levels of a particular unit, the level of research in a magic school, and the resulting spells available to your the units of your empire?