In the water -drowned city campaign accessory, 1-4 detectives reveal R'lyeh's mysterious and deadly city as it rises from the ocean. When you ventured into the grave -like ruins, you climb the crumbling bases of the city, search for foreign artifacts on the seabed, navigate between overwhelming machines and transforming corridors, and find a slice of ancient history that drowned with the city itself.

During the journey, you will experience a unique story that is dependent on the investigators chosen, which will culminate in a final battle against Cthulhu!

A dread in Arkham: the card game is required for the game.