Originally known as Myrdred--Myrdred was an Avatara that betrayed Damas,
Ravanna, and Connacht for powerful magic and spells granted to him by Mjarin (the Leveler). Henceforth Myrdred was known as the Deceiver. When Connacht returned as Balor, he raised Mydred back from the dead. Myrdred held no love for any of the Fallen Lords and was an ancient enemy of the Watcher.
The Watcher and Deceiver both had a duel after the battle of Tyr and the Deceiver was swept downstream. Mydred was injured and needed to be healed. The Warlocks were formerly his allies and decided to aid him and protect him when Soulblighter came to prominence. Eventually Alric had Myrdred healed of his wounds and in doing so, The Deceiver pledged himself to Alric's cause. The Deceiver fought his final battle with Shiver and though many say he was killed. Eastereggs and good tactical manuvers allow the Deceiver to survive the battle and his fate is ultimately unknown. The Deceiver could be a candidate for Alric's replacement of the Nine. But it is unknown if Alric tried to recreate the Nine against Soulblighter--it would be plausible given that Soulblighter tried to do everything Balor did as well.
The Deceiver could use the Binding Dream to bind living enemies to his will and control them, Myrdred could fire lightning bolts from his scepter and call down lightning from the skies. Myrdred could also teleport, use the death and decay dream, and could disintegrate enemies at close range. In Myth 3, Mydred could also use Dispersal Dreams and he has been hinted at using the Confinement Dream, a spell that buries people underground. Myrdred also was able to freeze many Trow in place via a powerful spell. What dream this was that Myrdred used is not known.