From publisher blurb:
This adventure supplement is a special collaboration with another creator we feel fortunate to call a friend, Dark Realm Maps. In Tomb of Two Gods, a group of level-8 adventurers hears about a recent tragedy in town. A local hunter came into town a few days ago and murdered numerous people in cold blood. All were caught unprepared to deal with the man's sudden outburst of violence. The constable sent a squad of voluntary guards to arrest the man in his lodging but none of them returned either. Now they offer a reward.
As the characters delve into this adventure, they shall discover that the hunter was not himself because of the influence of two strange entities in a nearby tomb. It is an ancient construction of elvish design meant to worship and understand the duality of the gods of the sun and the moon. A strange prophecy, related to these events, speaks of a time when both entities shall fuse and bring forth a time of reckoning for all mortals. The characters are now part of its fulfillment.
This is a level 8 adventure that leads the heroes to investigate a terrible crime, has them learn obscure truths about the nature of the world, and confronts them with a strange avatar that threatens to end the world as they know it.