Halfling Scales of War Campaign
Sarshan is the Shadar-kai that apparently rules Umbraforge. He is an outcast who made a name for himself as the leader of a legendary mercenary band known as the Black Arrow. At their height, the Arrow put so much fear in generals and kings alike that Sarshan would take payment to fight for one group then take a bigger payment from their foe to stand down.
Sarshan owns the tower, foundry, slave bazaar and forges of Umbraforge. Most of the mercenaries in the camps work for him as well. He currently seems to be doing a thriving business selling weapons and mercenaries all over the world. Sarshan apparently has access to a number of gates leading to other planes, including the prime world.