Mourel Duskwalker

Mourel Duskwalker was a star elf wizard who was corrupt and hungry for power. From his citadel of glass, Tir'in'tiral, in the demiplane of Sildëyuir, Mourel marshaled evil forces to conquer the star elves but was eventually defeated. He was interred in Tir'in'tiral and it, plus all of the towers connecting to it, were cut off from Sildëyuir to become a separate demiplane known as the Night Realm. Afterward, tales of The Duskwalker were became stories for frightening children.

History
Unbeknownst to the mages who cut it off, a portal that connected the Night Realm to the Yuirwood still existed, though it was inactive. In addition, Mourel's apprentice Kyjal Stardancer, who was the only survivor of Mourel's defeat, had managed to extract the brain of his master and placed it a jar of embalming fluid, and thus Mourel lived on as a brain in a jar. It was then placed in the chest cavity of a girallon zombie.

Around 1372 DR, a nilshai sorcerer Tolg'byri found and reactivated the portal to get to the Night Realm in order to muster an army with which he could launch his own attacks on Sildëyuir.

Unfortunately for Tolg'byri, his intrusion upon the Night Realm drew the attention of Mourel and the animated corpses also interred in the mausoleum that had been connected to Tir'in'tiral. These, along with Mourel's magical experiments and the undead remnants of his army began fighting with Tolg'byri's troops. Mourel also used the opportunity of his renewed link to the Material Plane to kidnap people during the night when the portal was active. He also managed to steal the Grail of Shargrailar from a merchant who had camped near the portal.

During the fighting, adventurers found their way into the Night Realm and put an end to the fighting by killing the leaders of both forces.