Savage Lankhmar - Knowledge Unbound
The Fabled Dark Sorcerer
Long thought deceased, Nagagie was an elemental sorcerer renowned for his magic prowess. Legend says he let the power of a Black Magic corrupt his mind, and he succumbed to evil.
He is said to be responsible for the unnatural Nagagien Spires found in the Great Salt Marsh, as well as the rolling pestilence known as Nagagien Bog Swarms.