"Dungeons & Dragons" is the source material of choice for PC role-playing games, and for good reason. The pen-and-paper game has survived three generations of revisions, and continues to unite nerds and Goths through a mutual love of the 20-sided dice. BioWare's powerful game-creating toolset named "Neverwinter Nights" takes place in the Forgotten Realms, a setting made popular by R.A. Salvatore's Drizzt Do'Urden character in the "Icewind Dale" and "Dark Elf" trilogies. Here the Underdark was first depicted as a cruel, underground world dominated by a matriarchal society of evil dark elves and inhabited by the foulest of creatures. Watch tonight's "X-Play" as we crawl deep into "Hordes of the Underdark."