Ashburgnul (Mor. "Eye of the Dark One") was a title held by the chief Sauronic Priest of the Morannon.
Though a mortal, he had artificially prolonged his life through sorcery – though his status as "alive" seemed debatable – and was several hundred years old. The garrison only referred to him as Ashburgnul, and most but the acolytes kept away from him except during rituals in the chapel.