Dagoth Ur

Dagoth Ur is the main antagonist and final boss of The Elder Scrolls 3: Morrowind. He is the "immortal" leader of the "House Dagoth", which consists of him and his armies of creatures infected by the Corpus disease, which he created, as well as his own kin and the seven powerful Ash Vampires. Dagoth Ur lives inside of Red Mountain.

The source of his power and immortality is the Heart of Lorkhan. At the end of the game this heart is found and destroyed, allowing the player to kill Dagoth Ur.