Zrach is one of many worlds discovered by the Vennans during their Travels on the River. While its location is known to all Vennan Travellers, it is rarely visited, due to its potentially dangerous environs. It is a land with dense forests and ground vegetation. Hot and humid, its frequent rains create numerous swampy regions.

Zrach has no sentient civilization but hosts a plethora of creatures, large and small, many of which are carnivorous. To date, no plants or minerals have been identified as favorable trade goods, and Zrach is viewed by Vennans as a world to be visited only with caution.