necropolis

The necropolis serves as the central command structure of the undead army. Lumber harvested by ghouls is processed, and loyal acolytes train for tasks from their undead masters. Even when unattended, the vengeful spirits of the dead protect the necropolis from enemy attackers. In time, this structure can be further modified to become the Halls of the Dead.^{W3Man 43} After that, it also may turn into a black citadel.