The planet has a number of Orbs covering the surface. The Orbs range in size, with the largest being 300 miles across.
The Orbs are the lifeblood of the Ilatim, with the loss of one Orb diminishing the planets population by 300,00.
The planet Thoreceus was terraformed by the Pac-Ha to make it suitable for habitation by the Ilatim. This included transferring as many Orbs as possible from the Ilatim homeworld to Thoreceus.
More recently, Thoreceus underwent a period of tectonic instability, resulting in the loss of many orbs and hundreds of thousands of Ilatim lives. The source of the instability was found to to be The Source, the god of the Flame. Sira the Unbidden, as well as Nerva the Unbidden, managed to convince The Source to relocate to Flameworld, saving Thoreceus from destruction.