The core setting of "Dungeons & Dragons" 4th Edition offers yet another origin for Asmodeus, identifying him as a former angel in service to a god only known as He Who Was. Asmodeus, as one of the greatest of the angels, was entrusted with leading angelic hosts in battle against the enemies of the gods. Though he served He Who Was loyally, Asmodeus believed that his deific master was far too forgiving and unwilling to use force. After the conflict, which came to be known as the Dawn War, Asmodeus was assigned to guard the entrance to the prison of the god Tharizdun which was located in the Abyss. The demon lord Pazuzu appeared to Asmodeus, as detailed in "Demonomicon", and encouraged the angel to act on his thoughts of rebellion against He Who Was. When Asmodeus was ready to rise up, Pazuzu aided him in obtaining a small piece of the shard of evil at the heart of the Abyss, which Asmodeus used to create his infamous Ruby Rod. Asmodeus returned to Baathion, the realm of He Who Was, gathered those angels who would join his side, and instigated a rebellion that ended with his former master's death. With his last moments of life, He Who Was cursed Asmodeus and all the angels who had followed him. The angels were transformed into the first devils, and the beautiful astral dominion of Baathion was transformed into a prison realm known as the Nine Hells of Baator. Asmodeus assumed the divine might of the fallen deity and became a god himself, albeit one trapped inside his own dominion.