According to Tamrielic Lore, the Fang of Haynekhtnamet is carved out of a tooth from a Wamasu by the name of Haynekhtnamet. Wamasus are intelligent reptilians with lightning for blood once living in Black Marsh. Before the dagger was created, a group of Nords killed Haynekthnamet during a fight that lasted seven days and nights, and then took the fang as a trophy. The dagger mysteriously contains some of the magic properties of the beast it once belonged to.
The dagger can be found in the large Sixth House Base of Mamaea in the final section, the Shrine of Pitted Dreams. The cave complex can be found in the West Gashregion, east of the stronghold Berandas, and just west of Daedric ruins of Dushariran.