From the publishers website:
When a rock formation on an old volcano looks like a human skull, you’re gonna get cult activity. Sure enough, a group of unholy bandits called the Obsidian Heart moved in and robbed the countryside blind for their dark god, until Saint Garth smashed them a century ago. But after some recent earthquakes, the cult is back, practicing kidnapping and sacrifice and pretty much demanding to be hunted down. Why now? Who controls them? Just how deep do the tunnels go inside… SKULL MOUNTAIN?
With 36 pages of adventure, 18 detailed maps, a new ritual magic system, and original fantasy art by Andy “ATOM” Taylor and Steve Zieser, “Skull Mountain” is an old-school dungeon crawl for fantasy games like Labyrinth Lord™. Recommended for four to six characters of 4th to 6th level.
Dedicated to the late Dr. Holmes and the imaginations a certain map inspired.