Thurvokun is a long-dead Dragon who once dwelled in the Dwarven ruin of Fang Lair. The necromancer Orryn the Black has discovered his remains there and is attempting to resurrect him. At the end of the dungeon, he will succeed in doing so and Thurvokun's undead skeleton must be fought.
In life his Dragon Priest was Zaan the Scalecaller, though he later abandoned her and the Dragon Cult to go to Arkngthumz-Phng and drive the Dwemer from it so he could inhabit it in isolation. He was one of the few dragons to have survived the Dragon War, until the adventurers Caluurion, Sabina Cedus, and Ulfnor slew him in the late First Era.
Once resurrected by Orryn the Black, the group will have to defeat Thurvokun. There will be Animus Crystals spread throughout the chamber, which can be destroyed to make the battle easier. Orryn cannot be attacked at this time, but he will cast a multitude of spells from around the balconies. Once Thurvokun is defeated, Orryn will merge his soul with the dragon's remains and take control of its skeleton, having a blue glow run throughout the insides of the dragon. Once Orryn is defeated, the battle will end.
- Casting the Bones: Investigate a necromancer cult searching for a long-dead Dragon.
- Pledge: Fang Lair: Prove you are truly Undaunted by clearing Fang Lair.
- Thurvokun was originally mentioned in Arena as part of the Fang Lair quest ("Legend has it that a Great Wyrm drove the Dwarves from their home in the Dragon's Teeth, and took the Lair for itself."), making him the first dragon mentioned in the whole series. However, he was not given a name at the time.
- Thurvokun translates to "Overlord Shadow" in the Dragon Language.