The Fortress of Zhon
This cave was found outside of the village of Dondenn. It’s inner chambers seemed to be an ancient meeting ground for the Cult of Taros. Perhaps it was kept secret or lay dormant for some time, though you couldn’t say how long.
Within it you found a number of disturbing items including depictions of a great reigning supreme above gods and mortals. The more you stared at these carvings and inscriptions the looser the grip on your own sanity became.
In the deepest portion you met Barroken, an evil and insane wizard bent on committing terrible acts to create abominations. His sacrificial altar looked like it had been in use for some time.