Haerinvureem

Shimmergloom is the nickname of Haerinvureem. He was a shadow dragon who arose from the depths of the Underdark after the Battlehammer dwarves of Mithral Hall delved too deep in their mithral mines. Shimmergloom drove the dwarves from their ancestral home, forcing them to resettle in the Icewind Dale region, and supplanted them with his Duergar servants. Shimmergloom reigned over the hall for roughly one dwarven generation until Bruenor Battlehammer, the rightful heir to the throne of Mithral Hall, returned to the hall in his adulthood in order to reclaim it. Shimmergloom attempted to retain his hold on the hall through the efforts of his servants, most notably, two shadow mastiffs, although he eventually had to confront the intruders himself, where he was eventually slain by Bruenor after the dwarf strapped a barrel of flaming oil to his back and jumped on to the shadow dragon's back. The ensuing inferno destroyed Shimmergloom, although Bruenor was unwittingly saved by carrying Drizzt's scimitar Icingdeath with him into battle, with the blade's magical protection from fire allowing the dwarf to ride Shimmergloom's burning corpse safely to the floor of the gorge.

Haerinvureem was the last survivor of the Jaezred Clan of Shadow dragons, who conquered the Drow city Chaulssin. After centuries of reigning and enslaving, the dragons were overthrown by their own offspring and most were killed. Only Haerinvureem managed to flee.