Necromancy

Necromancy is a sphere of magic that deals with death in all its forms. While necromancy isn't innately evil, the easiest uses for it will quickly lead those who attempt to learn it down a very, very dark path.
Necromancy is taught to a small subset of students Tyrness Academy, however the teachers carefully vet the applicants and don't allow everyone who wishes to learn it to do so. It simply is too dangerous to do otherwise.
Necromancy can raise undead by animating corpses with summoned fragments of ill will and dark feelings cast off by beings who have died. Worse, these fragments can't be banished like normal summons can be. Still darker magic allows them to remove a portion of the soul of one who recently died and corrupt the portion to use as the animus for a corpse, turning them into a far deadlier creature that has much of the skills and memories of the dead, while also tormenting the soul of the departed.
A necromancer with the proper spells can use their own life energy or that of another to heal, and with sufficient mastery, they can even restore the dead to life more easily than a life mage can. They can summon the spirits of the recently dead to question them, help put the restless dead to sleep, and control undead to keep them from killing those in the area.