Phobetor

Phobetor was the original center of the related cults of the Old Ones. When Mother Silvagis and her assassins meddled in the affairs of the Seraean Margrave Iovian during the Slave Wars, they incurred his wrath. He sent his most powerful agent, General Sept Luud with an invasion force to wipe them out, and nearly succeeded. 

This ended up not being the end of the Old One cults, however.  The remaining cultists decided to establish new cells throughout the galaxy, rather than be grouped together all in one location. Today, the Old One cults are relatively common, and their dark knights can be seen throughout known space. Although often allied with the Seraeans, the Old Ones remain completely separate cults from the way of the Shadow Knights, and in general do not acknowledge the superiority or authority of the Seraean Dread Council or the Emperor, although they certainly acknowledge his their political prominence. 

Despite this spread of the Old One cults, Phobetor remains their home planet, and many  make pilgrimages there at some point in their careers. Thriving Old One monasteries remain still on Phobetor. Their allies, the Shadow Knights, are occasionally welcome, as are—on rare occasions—knights of other orders. But the cults have become wary of other knights, and avoid or attack them most often, rather than deal with them.

System: Phobetor
Hex Location: 0619
Star Type: Double star, M2 V, T6 (distant)
Number of Worlds: 6
Gas Giants: 3
Planetoid Belt: N

Starport Type: D
World Size: Earth-sized
Atmosphere Type: Earth-like
Surface Water: 40%.
Population: Medium (200 million)
Political Affiliation: Independent, but allied with Seraea
Notes: With a super-close, but cool red sun, and a more distant brown dwarf as the only sources of light and heat, Phobetor races in a tiny orbit around its star, but remains relatively dim.  Thick mists cover much of the planet.  Because of this low light condition, traditional plants struggle, but big, thorny trees exist that release strange red spores that glow very dimly with a biological phosphorescence as they do chemosynthesis in the mist.  They then transfer this energy back to the trees that they brush against it as they drift.

Xenohumans live here, and have since recorded history for the planet.  They appear very similar physically to the native Seraean race; chalky white skin, with black hair and dark eyes.  In spite of this, genetic studies show them to have lived here in isolation for a long time, and they are not closely related at a haplogroup level with the Seraeans.  For the most part, they live in the swampy, forested lowlands, deep in the mist.  Most of the non-natives who live here, on the other hand, prefer to claim the dry Uplands, above the mist, and devoid of most plant life.

Most of the native humans belong to the Old Ones cult.  In the past, this was strongly matriarchal, but today that is less true.  The Pontifex Sacrorum of the Cult for the surrounding area lives in the city of Shuruun, deep in a massive rift valley; a "Valles Marinaris" for Phobetor, where the mists are the thickest on the entire planet, perpetually surrounded by a dull red darkness.  Nearly half of the rest of the native population lives in towns and cities around the edges of the valley, also all called Shuruun, but with a designated number following (such as Shuruun 083) but the rest are more widely scattered.  The inhabitants of Shuruun are largely rentiers who service the religious observances and piety of the Old One cults.  The productive members of society—the farmers, ranchers, craftsmen, hunters, etc. tend to live more scattered across the surface.