There are ten primary schools of magic in the world of Rebirth of the Fallen. In most cases, people can study as many as three schools at a time. Casting spells takes a certain amount of energy. In the novels, the amount of energy a character can spend is referred to as their ‘well’. A person’s well gets deeper the farther they progress in each of their schools of magic. Magic items can also deepen a caster’s well. Finally, some, but not necessarily all, spent energy is recovered each time a person sleeps.