Turok Han

Turok-Han (also known as “Übervamp") is an extremely strong ancient vampire. It was turned into a demon when the human was still a Neanderthal. In Bring on the Night, Giles says it was known as the “vampire other vampires fear". The First resurrected the Turok-Han using the Seal of Danthalzar and created an army of them to fight Buffy and the Potentials. Buffy discovers an ancient Slayer weapon she names a scythe which kills the Turok-Han with relative ease.

The original Turok-Han was played by Camden Toy, who also played one of the Gentlemen and Gnarl.
The Turok-Han (aka UberVamp) was first seen in Sunnydale in BtvsSeasonSeven as an agent of TheFirstEvil. They were the original Vampires before Humans came to be. They are much stronger than Human Vampires, but sun light and fire can kill them, and they can be staked and beheaded. However their body has thick armour which makes this very difficult.
Interestingly, the Turok-Han are completely immune to HolyWater, Crosses, and assumingly the Bible, all of which burn Human Vampires. In fact, this small detail sheds a lot of light on the subject of Vampires.

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