From publisher blurb: This module has lain unseen and forgotten in the TSR design vault for twenty years. Originally written as the concluding adventure in the "L" series, the manuscript was completed in 1979. As a part of the celebration of the Silver Anniversary of the Dungeons & Dragons game, we've unearthed this classic adventure and present it here for the very first time - the last first Edition AD&D Module ever to be published! Your party of stalwart heroes must venture into a lost dwarven mining complex, fighting terrible monsters, bypassing deadly traps, and exploring chambers heavy with the dust of ages. Somewhere deep below the surface lies the heart of darkness - a corrupting evil that must be stopped before its influence can spread! An adventure for characters levels 3-6.