The Thanatia system is a solar system with a standard yellow star, four normal planets and a binary planet, essentially two planets joined together. The planets of the Thanatia system are teeming with life and resources, but are mostly cordoned off and kept off-limits, due to how dangerous that life and those resources can be.
The only publicly accessible planets are Thanatia 2 and 3, which allow all races to visit. There are several small colonies for various non-Thanatian races on these joint worlds. Cassidia is the Cassid homeworld and is often considered off-limits to outsiders unless they get a permit to visit or live there first. Thanatia 1 and Thanatia 5 are considered property of the Thanatians, Thanatia 4 is considered property of the Banikans, and no other races are allowed to even visit, let alone settle there.
The planets of the Thanatia system are:
Thanatia 1
Thanatia 2 and Thanatia 3
Thanatia 4
Thanatia 5
Cassidia