Those who follow Vecna and Mask hold alliance in the Covenant of Shadow.
Seeking and securing the ancient arifacts and magics of the world, the great vault of Vecna sits in the heart of Mishtan's undercity, Nocturne.
Despite the evil alignment of the ruling deities, the CoSh primarily concerns itself with neutral objectives; doing what is necessary to acquire what they are after, without causing so much disturbance as to rally the interests of others. Working in relative stealth is a facet of their cause. "Don't draw attention to yourselves unnecessarily."
The CoSh has until recently held a position within The Collective. With the death/entrapment of Artemis, and then disappearance of the other members, Dathkel and what's his name, the CoSh has lost their footing within The Collective.