Dokyúumi

The Dokyúumi is also known as the Poison Sea. It is a disk of poisonous salt water that surrounds the four islands of Rokushima Taiyoo. No sailors will risk sailing on Dokyúumi due to rumors of the monsters lurking beneath its surface.

Data from the Ravenloft Catalogue

		Ravenloft Third Edition Ravenloft Campaign Setting Heroes of Light
		Ravenloft Third Edition - p170 Ravenloft Campaign Setting:Domains and Denizens - pp39-40 Heroes of Light - p83
		Ravenloft Third Edition - p171 Ravenloft Campaign Setting - poster map
		Poison Sea