The Sea of Rot
This 50-foot-deep, 3-mile-wide rift circumscribes Deadhold like an equator. The Sea of Rot is so named because it is filled with a seemingly endless legion of zombies. Mortal creatures offered as sacrifices to Orcus have their spirits reborn here as conscripts in the Shambling Horde. When Orcus has need of a zombie army, he creates a portal from this place to the battlefield.