Necromancy.

The most feared and most misunderstood school of magic. It allows the user to bend life and death to their whim, turning the living in to soulless husks and the dead into undying minions.

It also, incidentally, leaves said minions... lacking in intelligence, wisdom, charisma... a lot of core stats, actually.

Not to worry, for the [Undead Lieutenant] and [Awaken] spells are here! Perfect for giving your unwilling minions true intelligence with which to better serve you and lead their fellows.

For the side-effects of giving your undead minions sentience, please consult system help menu 110-C

(CWs so far: R*pe)