The Gray Goblin Warrens

From the introduction: Recognizable by their rock-gray, wart-covered skin, the gray goblins have long been a scourge upon the local area: raiding villages, stealing livestock, attacking merchant caravans, kidnapping your maidens, etc. The goblins lair in a network of caves and tunnels beneath Hags' Tor, under which is also rumored to be the lair of a red dragon.