Therys Saroscient, more commonly known as Therys Trollfriend or Therys the Traitor, is the father of Aerdon Saroscient, a former Watcher of Shade Vale, and an exile of the wood elves.

Once, he commanded the Watchers of Shade Vale. But his wife fell ill with rotlung and he consorted with the trolls in a desperate attempt to find a cure. Myr Stonegaze exposed Therys and launched an inquiry. Therys, fearing for his family, fled Shade Vale.