I've been reading through the Starfinder source book, Pact Worlds. It's a small book, but fits a lot of information into it, so I'm going to post about sections as I finish them.
Eox is the eighth celestial body from the sun in Golarion's solar system. Unlike the two previous entries, Eox is actually a planet. Admittedly, it's a dead planet, but it's at least in tact.
The inhabitants of Eox are mostly undead, and have been since Pathfinder times. How long ago is that? I have no idea, because there's the Gap that disrupts any understanding of the game world's timeline. I assume that this means Eox isn't a very technilogical society, or at least what tech they do have must have been developed or purchased in the few hundred years after the Gap. It's difficult to judge how far Eoxian society progressed from what we knew of it in the Paizo Distant Worlds source book, so it's up to the GM must theme the world.
Eox was featured heavily in one of the modules in the Dead Suns adventure path, luckily, so I felt pretty familiar with the world before reading this section. I do feel that I got some extra ideas about specific locations and factions, though, so like Castrovel I feel like this one does a good job of covering an entire planet while still managing to impart useful game information.
The Eoxians make up most of the population on Eox. Before Pathfinder's time, the planet suffered a cataclysm that wiped out the entire planet's ecosystem and population. However, the Eoxians saw it coming, so the bone sages (I'm not sure whether they were called bone sages then, but that's what they would become, anyway) transformed most everybody into undead.
Aside from Eoxians, there are some androids who live on the planet, which is possible because androids can survive without an atmosphere.
Between the material in Dead Suns and this section, there's plenty of data to work with when planning for an adventure on Eox.
The planet is a radioactive wasteland, and has been for a long time, so I doubt there's much of the old world left. I think you could argue that there are some undiscovered remnants underground or in the sides of cliffs or mountains, but canonically there's no suggestion of that.
Eox society is structured around self-contained regions, each ruled by a bone sage. How the bone sage rose to power varies. The Festrog Queen, bone sage of Karus, earned her city through politics. The Painted Lady, bone sage of the Necroforge, simply has a great industrial research complex and probably always (for all practical purposes) has. Tzurrtk, the bone sage and founder of Exantius, built a city. The Soulless One, of city Thanox, siezed power after the Gap because, I guess, the Gap caused there to be a power vacuum there. It's not at all clear how or why the Gap caused a power vacuum in Thanox, but that's what the books says (I mean, that suggests that there would be power vacuums elsewhere after the Gap, but this is the first mention of it. It's enough to make you think that the Gap makes no sense.)
The major city on Eox, at least for most players, is Orphys, which is enclosed and has been provided an artificial atmosphere specifically to house living guests. Eox has places of governments, it has religious institutions, industrial complexes, research centers.
The location I find most intriguing are the Catacomb Mountains, a manufactured structure containing tombs warded by runes and security systems. Nobody knows who built it or why, and exploration is officially forbidden. However, there are rumours that research teams are sent in sometimes, but nobody can say what, if anything, they learn. This is obviously begging to become your game group's next quest.
I've decided that the Starfinder worlds need shorthand descriptions, the way one might refer to Magic: The Gathering planes by theme. Innistrad is gothic horror world, Theros is Ancient Greece world, Ravnica is city world, and so on.
My first impulse for Eox was to equate it to the obvious post-apocalyptic material like The Road and Fallout 3, or even Dark Sun. But the civilised undead element is pretty unique, and rarely do post-apocalyptic nightmares have kindly undead hosts offering you a place to stay in a bubble city with free clean air for you to breath. It just didn't seem to fit.
Then it ocurred to me: Eox is actually Hyperborea (the setting of the Robert E. Howard Conan the Barbarian books.) Fiefdoms with leaders with their own goals and tenuous alliances, separated by threatening countryside (or wastelands, in the case of Eox.) There's not much talk of wandering monsters on Eox (I assume they're all dead), at least not in Pact Worlds or the Core Rulebook, so I think the main threat out in the wasteland is unfriendly undead, or agens from enemy cities. I don't get a good sense for the level of technology on Eox, which means that it's open for interpretation, so I'd probably go with cyberpunk, because that's a favourite sci fi setting of mine. The end result? Cyberpunk Hyperborea.
So far, this is what I have:
Next in line is Triaxus.
Header photo by Seth Kenlon, Creative Commons cc0.