The party is able to solve the mysterious puzzle in the cavern, activating a portal in a nearby pool of water. After entering it, the group finds themselves within the Gloam, a mirror plane of shadow and muted emotion. It is a dangerous place, though not a necessarily evil one.
The party presses on, encountering the flora and fauna of the Shadow Underdark. Upon exiting the caverns and entering into the Underdark wilderness proper, the party realizes they are being followed. They hatch a clever plan to bait out an ambush, and catch a group of twisted Duergar. Their madness clouds any ability for a diplomatic solution, and a battle ensues, leading the death of the Duergar and the discovery of a coinpurse, fattened by Dark Elven coins.