Nye was on Mevolent's side during the war and enjoyed performing horrible experiments on those captured, often torturing its victims to death.
Bizarrely, Nye was first found working with the Headless Horseman in a place where there was no life or death. Valkyrie went to it on the advice of a banshee to have it seal her true name. Nye did so, but betrayed her after the Headless Horseman left.
It tried to find her soul, as it did with many other people whose bodies surrounded its workplace. However, it did not get enough time. As there was no death in Nye's home, she lived even after it removed her heart, though she could not use magic. Once she regained her Necromancy ring, Valkyrie used death magic while she was dead to subdue Nye and force it to fix her.
Nye later appeared and is now a medic for the Sanctuary, taken on after Kenspeckle Grouse's murder at the hands of Clarabelle after a Remnant took over her body.
It agreed to give Vaurien Scapegrace and Thrasher the zombies new bodies, getting the White Cleaver as payment after Lord Vile tore it apart.