Cursed Fang of Sithis

The Fangs of Sithis are very powerful twin daggers given to the Night Mother by her Dark Husband. They possess devastating power but at the cost of the user's mind and soul.

The Shadowscales model their weapons after them.

They were recovered during the late Second Era by the Argonian relic hunter Looks-Under-Rocks and his dunmeri partner Barvyn, the later of which went mad after attempting to wield just one of the fangs.

The second fang somehow ended up in the hands of the Renrijra Pirate Captain Nahrevil, who then used it to slaughter her entire crew before setting the ship they were sailing on aflame.