Once a pleasant and temperate planet covered by water over 97% of its surface, Krrendar IV is now a hellish world where surface temperatures exceed 600 degrees Celsius. Blame for the catastrophic change goes to the aboriginal Nightsider population's reckless industrialization and environmental devastation. The Systems Commonwealth's Ministry of Environmental Reclamation tried without success to reverse the damage, but eventually the Nightsiders had to be evacuated and the planet ceded to the Pyrians, who have further "pyroformed" Krrendar IV to meet their own requirements for habitation.