Vaporius

Vaporius is a heathen desert world within the Moronus Expanse in Warhammer 40,000. It is ruled by a Caste of psychic Priest Kings, and the people are mostly hairless, tan, and cyan-eyed. The cities of Vaporius are made of glass and copper; the deserts are in a multitude of hues of sand. The small seas are made of acid, and water drawn up by the Priest Kings from deep underground is actually a parasitic xenos lifeforms. Silicon-based rock monsters live in the mountain ridges of Vaporius, and in deep caverns beneath the sand, exiled mutated non-Priest King-psykers who drank the waters of Vaporius called The Unquenched dwell. The Unquenched drain water from whatever they touch, but are never satisfied, and even if they are without Waterford long enough that they collapse into dust, they are unable to die, instead becoming a cursed location of floating dust that sucks the moisture out of whoever enters it. Only psychic attacks can destroy The Unquenched.