He is the most active god in the drow pantheon since he feels that he is on the verge of becoming an intermediate god, and that means that he must soon come to a confrontation with Lolth. The omens he sends to his priests are either in strange moving shadows or even occasionally with a nightmare to deliver them.

Like many other powerful creatures of the lower planes he decided to increase his power into the prime material world. Unlike others before him he was not involved in the blood war so he was free to do it in a very dramatic way. He is the Lord of the Nightmares and to gain a foothold in the prime he created the first of the Black unicorn, an evil unicorn, and entered the unseelie court. Seeing that the drow are subtle enemies like himself he decided to become one of their gods and managed very well since then. He is the main plotter of Lolth's downfall along with the other 4 drow gods that oppose her (Kiaransalee, Vaeraun, Ma'azbert and Ergosal). 

Duties of the Priesthood
They are to encourage the use of the subtle arts of magic (namely illusions, charm, and shadow), and inspire fear in the hearts of their enemies
and the enemies of the drow race.

They cannot have more than half of their spells from every level taken from the mage schools they are granted access to.