The Mines of Bloodstone is a 1st edition Advanced Dungeons & Dragons adventure that was later retconned into the Forgotten Realms. It features the Battlesystem tabletop rules.
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The most deadly dungeon ever devised! High-level characters brave the unexplored corridors of Deepearth to confront perhaps the most feared adversary in the AD&D game.
The second chapter of the Bloodstone Pass saga follows the conclusion of the desperate war against the bandit army. A cold and bitter winter drives the villagers to the edge of starvation, and numerous horrors strike the town of Bloodstone Pass.
Join the adventure as the heroes explore the depths of the ancient Bloodstone Mines, now inhabited by fearsome demons. There they hope to uncover the fantastic treasures rumored to exist in the unknown darkness. But deep within the mines, all is not what it seems...
This module uses the new rules from the Dungeoneer's Survival Guide and Wilderness Survival Guide. The adventure also includes optional BATTLESYSTEM scenarios fought entirely underground. These supplementary products are not required to play the adventure, however.”