Nyx was the last leader of House Silvermoon before its fall during the Hundred Years War. The House was once a group of doctors and scholars which served the Queen's court, with magic themed on the Moon's associations with comfort and healing. As the War dragged on, Nyx made the decision to officially appeal to Royal Vanilla for an end to the conflict and suffering, but she interpreted it as a sign of treachery and ordered the elimination of his House as punishment. Thus were the grounds of House Silvermoon destroyed and its members were either executed or exiled from Treatropolis.

Known as a gentle, erudite and calm soul, he developed various restorative techniques and often ventured out of the House estate to teach and help where he was needed. He is presumed dead by the general public, and presumed missing or in hiding by his close friends and relatives. His brother, Erebus, is currently searching for him throughout the Dream and Nightmare Realms.