Lair of the Udyrfrykte is a cave found in The Elder Scrolls III: Bloodmoon. The Lair is a small ice cave on the eastern shore of Lake Fjalding in the Felsaad Coast region.
The cave is part of the quest "The Mead Hall Massacre." It can only be entered if "The Skaal Test of Wisdom" quest has been completed, otherwise, its entrance is blocked by snow.
Inside lives the Udyrfrykte, a beast that has killed the chieftain of Thirsk and most of its clan members. He drops a severed Nord leg and the Heart of the Udyrfrykte.