The Wraith is a elemental being originally from the Argent D'Nur dimension until it was absorbed by Hell. They were deified and feared by the original people of the Argent D'Nur and protected by the finest warrior order of the dimension, the Night Sentinel as a means to harness their tremendous power as a energy source and defensive measure against then. During the war, they gave the Sentinels necessary power to defend the realm from the Hell Legion. However, one Hell Priest by the name Deag Grav and his cabal used the Wraith's essence against them with the help of a traitorous Night Sentinel (it is highly assumed to be the Doom Slayer himself) by forming the Well, which enables the Hell Legion to gain an upper hand and finally victory over the realm. After their world was absorbed into Hell, their souls was trapped in the Hell energy sphere until the Doom Slayer uses the Crucible to free them.