"Let me continue. Performing magic with a circle always leads to success in the spell. In the center of the circle you must draw the actual spell that is to be performed." he took a pen and paper from a chest he had in hut and started drawing "These characters represent an explosion, the number of these symbols represents the number of explosions, the size of that character in relation the circle as a whole represents the power. Of course, things like time delay and the explosions having varying power can also be edited. I will show you these things someother time. The important thing about magic circles is that no matter what, you can't power them from your soul and you need a material source of energy. There are two possibilities for that: living and nonliving, and they are drawn differently. Living here refers to beings with some resemblance of soul, which is why most plants, expect for the druids and some others,don't make the cut. The best example for nonliving power source is fire.