The Magisterium are the rulers of the Shapeless empire. They are chosen by the Shapeless During the events of the First Weaver Saga, Roirr 'jumps' into a magisterium member. He proceeds to kill the rest of the Magisterium. It is unknown what happened to the Shapeless Empire after the events of the First Weaver Saga Roirr says that the Magisterium Members develop unusual powers, like Plasma Magick, due to their close proximity to the mana core