Sumyu Elzo, commonly known as Engan, is a duergar warlock criminal famous in the Underdark, and is one of the leaders of the ithre smuggling ring taking place there.
In the series Edit
Engan's first and thus far only appearance was when the party reached the cave he and Paya Praxél were using as a base of operations for the ithre smuggling ring. Being in possession of five yeth hounds, he ordered them to fight the party while he cast spells at them from the back. Shortly after casting Sickening Radiance, he was knocked unconscious by Atonus Sepa using a Lightning Leap from his Mastery of Weather discipline, as his brother Marosi Elzo had requested that the party return him alive.