Rise of the Demon Lord
Illidus The Betrayer
Legend has it that, many centuries ago, an Eladrin Warlock named Illidus made a pact with a very powerful demon. Through arcane rituals learned in the Underdark, Illidus was able to steal the demon’s power and began waging a war of destruction across the land. A band of adventurers managed to use a magical item called the Skull of Hamfel to weaken Illidus to the point where he could be banished to a remote section of Hell, trapping him there for eternity.
The truth is that Illidus the Betrayer was the demon patron of the eladrin Warlock Salissta Stormrage . The demon was trapped in an ancient ritual by Salissta, and his essence was absorbed by the Warlock. He was physically destroyed in the process, but the demon’s essence corrupted the eladrin even further. Horns sprouted from her head, her eyes took on a devil’s glow, and her dark hunger for power was made exponentially stronger.
The demon is gone, but his curse lives on in his host.