Onyx Prison of the Demon King (OSR)

Legends tell of Blackshard Hold—a dwarven redoubt nested far to the south, in the all but impenetrable Forest of Gray Spires. The dwarves of clan Kildare built the hold around a vast monolith of glimmering black onyx. For years, they dwelled there, mining the precious stone and accruing wealth from trading with Dulwich, Wellswood, and even the city of Languard, far to the north. Then, Kildare and his kin suddenly abandoned Blackshard Hold, claiming some eldritch horror lay imprisoned therein. Hah! As if dwarves wouldn’t tunnel to the very depths of hell itself if there was any gold to be won! Mark my words, adventurers—those tall tales of captive demons are nothing but the cheapest of wards, meant to dissuade the faint of heart. There’s precious onyx in that old burrow yet, and it belongs to the brave! This Dungeon Backdrop is designed to work with the Lonely Coast campaign setting but can be easily inserted into almost any fantasy campaign.