The Second Darkness Adventure Path comes to its explosive conclusion as the heroes travel into a forgotten world hidden deep underground — the Land of Black Blood! There, they must contend with the region's monstrous guardians and defeat the drow who would use ancient magic to call down a star from the sky to destroy their enemies on the world above. This volume of Pathfinder also includes a gazetteer of the deadly Land of Black Blood, an exploration of the demon lords of Golarion, a bonus adventure set in the deepest reaches of the underground world, and several new monsters from these dark depths.