The Shade Isle Campaign
Shade Abbey is a temple-complex delved into the western face of Thunder Table. A short distance from the front doors to the abbey, a lake about three leagues across (the Highmere), which is fed by a waterfall from the north leg of the Schönflow river, here empties into the south leg of that same river. An island (yet unexplored) sits in the middle of the lake, and a large hill with visible cave-mouths sits across the river on the Highmere’s southern shore.
Shade Abbey is home to the priests and other devotees of the Church of Acrefatum, by all accounts an evil religion whose followers worship a sinister god of fate and death called Domstag. The abbey priests routinely send out patrols of guards to round up travelers and whoever else they can find on the road, in order to bring them back to their temple as slaves, sacrifices, or new converts.
The player characters recently discovered that (a) Shade Abbey is in league with Dolheim, trading magical items called mana stones to that country in exchange for a steady supply of prisoners and slaves to keep Shade Isle populated; and that (b) the mana stones themselves are made within a device called the Soul-Still, which uses human souls to power the creation of said magical items.