Black Tower of Vrackmul

The Black Tower of Vrackmul was the home of Vrackmul, a powerful but insane necromancer. His destruction unleashed powerful necromantic energy that is said to have powered the creation of his twelve skull lords. The Black Tower was also obliterated, its ash said to have coalesced into the skull lord's substance. It is unknown if Vrackmul somehow willfully orchestrated the creation of the skull lords or if they spontaneously arose on their own.