Human Folks
I'll describe the cosmology in a later blog entry, but for now, let me just say that the world exists at the convergence of 6 axes. Picture an octohedron like a d8 with a vertex pointing up. The top and bottom points are the Primordials: Light and Dark. The four points around the middle are the Elementals: Fire, Earth, Water, and Air. The physical world exists in the center and is composed of a mixture of all 6 in varying proportions.
The folks of Tellus and its moons are all composed of the 6 forces, but none are an even mix. Some lean more toward Fire, others toward Water, and so on. I use the word "folk" or "kin" for what D&D usually calls "race" because D&D races are really more like species than races. "Species" is a medieval word, but it still feels out of place to me, so when you are distinguishing between humans and elves, you would say they are different kin or different folks. If you were distinguishing between two different ethnicities of elf, you could call those races, in theory; in actual practice, nationality or religion tends to matter more than ancestry.
Humans
Humans are the closest thing to an elementally neutral kin. There are humans aligned toward every element.
- Fireborn have black eyes and skin in the colors of burnt wood from charred black to light grey ash. Nearly all have hair in a reddish hue, but orange or yellow hair is not that unusual. They are stereotyped as ambitious, passionate extroverts, but even the introverts tend to be described as "quietly smoldering" (because stereotypes are mostly bullshit, but people still want to put everything in a box anyway).
- Earthborn humans typically have the coloration of igneous rocks. Their skin can be black, dark red, light pink, or white. Their eyes are black, reddish brown, or dark green. Their hair can be black, white, or "salt and pepper". They are stereotyped as rugged, square-jawed, down-to-earth, reliable people. (Of course, there are "exceptions that prove the rule" that are usually dismissed with references to earthquakes and sudden rockslides.)
- Waterborn humans have a distinct blue-green skin tone ranging from deep midnight blue to light seafoam green. Their hair is universally green, but in a range of shades from pale sage to almost black with a green sheen. Their eyes are blue, green, or grey. They are praised for being flexible and adaptable (while at the same time, being criticized for being wishy-washy and noncommittal).
- Airborn tend to be quite tall which makes them look thin even when they aren't. They get described as "willowy" a lot. They have cloud-colored skin ranging from dark storm clouds to the whitest fluff, though most tend to be a light overcast grey. Their eyes and hair are the same cloud color, but their eyes are darker than their skin while their hair is lighter. Some airborn with very dark skin have extremely light eyes and hair referred to as "lightning haired". Airborn are assumed to be flighty and mercurial. They are often seen as soft and gentle and when they take a strong stance on something, their strength is dismissed as empty boasting. More than one tavern bully has found himself on his back after accusing an airborn of being all talk and receiving a lightning quick strike to the jaw.
- Dawnborn and Nightborn are what might be called aasimar and tieflings in other D&D settings, but without the inhuman extras like horns and tails. Whereas the Elemental varieties of humans have colors that we would consider unnatural in the real world, the Dawnborn and Nightborn come in all the normal shapes and colors that we see on the street every day. The only significant difference is in their eyes. Dawnborn have wide but extremely narrow eyes with long lashes — so narrow that it's difficult to know if they are closed or open just enough to look at you through their lashes. Nightborn, on the other hand, have unusually large, wide eyes that rarely blink like they are trying to take in every bit of light they can. (Now that I type it out like that, I'm suddenly realizing they have the ultimate "Vixen" and "Doe Eye" look.)
Oddities
Dawnborn, Nightborn, and the elemental humans all "breed true". If two different types of humans have a child together, the child will have features from each parent but will have the elemental alignment from only one parent. For example, if a short, stocky, granite pink Earthborn father has a child with a tall, svelte, ash grey Fireborn mother, the child might have the mother's height and the father's broad shoulders, but the child's skin and hair coloration will either be fully Fireborn or Earthborn (sorry, no magma babies).
There are, however, some human types that aren't inherited from their parents. It seems unfair to call them "mutants" or "tainted", but they are the result of the environment where they were born. Most humans in the nation of Aquilan are fireborn because it was founded long ago as a fireborn kingdom and fireborn still make up the majority there. An Aquilannie fireborn is a fireborn because their parents and grandparents were fireborn. If their family had moved to the neighboring kingdom of Almarune, they would still have been born as a fireborn. On the contrary, a Ghul from the mountains ringing the Cruachin crater wasn't born a Ghul because their parents were Ghuls: they were born a Ghul because they were born near the Cruachin crater.
Ghuls
Ghuls are classified as Shadowborn by scholars who study such things, but nobody calls them that outside of an academic context. Because of the influence of "underdark radiation" during their gestation near the Cruachin crater, Ghuls are aligned toward the Umbra (sometimes called the Fell Realm or Shadowfel), a dreary "Half Realm" between the tellurian world and the dark Hell Realms. They look like skeletons because every part of a Ghul's body is completely invisible except their bones, nails, and the hair on their heads. As a people, their culture is very egalitarian and they judge everyone on their individual deeds and accomplishments. Outside of their homelands, they are often regarded as uncouth hicks or barbarians because they lack any pretense at formality and tend to favor nudity if weather permits. (They are definitely the kind of people to wear a t-shirt and shorts in the early spring when everyone else is still wearing sweaters and jackets.) They favor unusual hairstyles with complex arrangements of braids and facial hair and painted nails because it is the only way that they can look distinct from other Ghuls. Some who travel among other nations wear makeup or body paint to hide their bones for the comfort of others, but most don't like doing so.
Feyborn
What scholars have dubbed "Feyborn" are sometimes called "wildborn" or "fey-touched", but they are most commonly known as "changelings". Changelings are much less numerous than Ghuls, but they are much more widely distributed across the world. All Ghuls are born in or around Cruachin, but feyborn children occur near passages to the Gloaming, the Half Realm between the tellurian world and the light Heaven Realms. These passages are uncommon but can occur almost anywhere (usually in out of the way places, but an urban passage is known to exist at the end of a narrow alley in the city of Cadwael). They only open intermittently, so not all children born near one will be Feyborn.
Feyborn look like the majority of people around them: not just the people where they were born, but the people anywhere they go and spend a significant amount of time. A feyborn's appearance gradually shifts to match those around them, sort of like a chameleon. Some feyborn learn to consciously control this chameleon effect, but each feyborn has a "tell" that shows their true nature. Usually this is a distinctive feature like a forked tongue, an extra finger, or irises so large their eyes have no whites. Nobody knows what a feyborn would look like if they were far enough removed from other people for a long enough time.
The Alchymists
Today, the kingdom of Aquilan is henotheistic: other gods exist, but they exclusively worship Verath as the state religion. The Temple of Verath in Aquilan split off from the Church of Light, which still worships Verath as one of a trinity of deities. One of the causes of this schism was that Aquilan was full of many different sects and mystery cults. The Verathic order felt that the Church should be doing more to "discourage" these other religions, but the Morrowan order said the Church should just try to attract more worshippers by setting a good example and the Saphyran order wanted to live with other faiths in harmony. The Verathics preferred a more direct approach and so they established the Aquilannie Inquisition.
Some of the most visible cultists targeted by the Inquisition were the biomancers of the Transcendental Alchymical Order, commonly known as alchymists. The alchymists experimented on all manner of strange beasts: injecting them with drugs and potions, crossbreeding them, vivisecting them, grafting parts from one to another to create a more perfect form. They even performed the same experiments on their own bodies (and less enthusiastic "volunteer" subjects) in pursuit of biomantic enlightenment. The Inquisition came down hard on the alchymists when the full depths of their depravity began to come to light, so the alchymists fled in a mass exodus to the east.
In the great forests and plains of Agored Baith, the alchymists harvested new raw materials from the great forest beasts and "recruited" new membership from the Geltic tribes for a time. Eventually, rival tribes put aside their differences and formed an alliance with bands of forest wolfen and dwarves from Tir-Tan-Gir to drive the alchymists further east out of Agored Baith and south of Brin-Ni-Au into the desert of Drits. The alchymists not only survived but thrived undisturbed in the desert.
Today, one may occasionally encounter student preternaturalists from the Transcendental Alchymical Order collecting specimens to bring back to Drits for further study. They may be in a city to procure odd reagents, live beasts, or preserved body parts. Sometimes they are encountered in the wilderness accompanied by hired bands of mercenary hunters looking for interesting game. More rarely, one may encounter a fully initiated chirurgeon trying to hide their grafted carapace and extra limbs under a voluminous robe (which is pointless, because they never seem to consider hiding their biomantically augmented "pets" that they bring along as bodyguards and guard dogs).
The alchymists are basically what I came up with when I thought "What if the Borg used magic potions and grafted monster parts instead of cybernetic super science?" They allow for a few extra wrinkles in the classic "save the village from the monster of the week" adventure. Sometimes the weird "a wizard did it" monster is something that escaped from the alchymists or was intentionally released as a test. Sometimes when you're trying to hunt down the beast to save the village for the bounty, one of the rival hunters is an alchymist who wants to capture it alive. Or, maybe they want to team up in killing the beast and will let you keep their share of the bounty in exchange for certain parts of the carcass. Or, maybe they just wait in the village for you to collect the bounty and then offer to buy the carcass in a really creepy way that makes the PCs wonder what they want with it. I've never had a PC alchymist in a game yet but it's always fun to have one as an NPC to surprise the players with new creepy weirdness like "the 'extra pair of longswords' under his robe are actually a big pair of giant mantis scythes... roll for initiative" or "it turns out his breath was so sour because he can spray acid from a gland in the back of his throat... save vs breath weapon".
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