The Wyverntongue Chalice was one of the relics of The Nine. It contained the spirit of Treth Halonter who could be called forth by the chalice's owner. Treth's spirit was forced to obey the commands of the owner.
The chalice was displayed in the royal palace in Suzail for many years but was stolen as a drunken prank by Nethglas Stormserpent sometime in the 1470s DR. When the chalice's theft stirred the war wizards into a frenzy, Nethglas became worried and stashed the chalice in the Chamber of Wyrms Ascending in the palace. In 1479 DR, his younger brother, Marlin, retrieved the chalice from the palace. Marlin called forth Treth and Relve Langral's spirit from the Flying Blade and sent them on a killing spree through Suzail.