Welcome to Gaia! ::

1. Dragonkin: When dragons first discovered humans, they were so fascinated by them they took select individuals and bred with them, carefully engineering everything until the dragonkin were born. They chose only the most intelligent and strongest, creating a hybrid that was neither one nor the other. Magically they are one of the strongest races, falling just behind dragons and elementals, and drawing even with demons and elementia.

2. Celestial: Angels wind up breeding with humans for varying reasons, each reason as unique and personal as the people involved. Celestials are amazing people, great diviners and often prophets. Celestials are always tall, almost always abnormally tall because of the angelic blood running in their veins. They are kindhearted and easily hurt, often taking up roles in human society to help others in need. They are doctor, caregiver, friend, lover, everything and anything you could need all in one. Their magic is very limited compared to the other races however, focusing mainly on healing and divination.

3. Faerie: Faeries live in a world parallel to ours, just a thin veil separating us from them. However, many faeries live in our world too, for reasons of their own. Their magic is heavy in glamour and scrying. Faeries are the third race. They are equally dispersed between their realm and faerie. Faeries are the most likely to interact with humans; indeed, only humans are more versatile than they are. It is not uncommon for a faerie to take a human as a mate. Faerie blood is dominant in all cases, but the faerie’s abilities are changed depending on what they breed with. A faerie/elemental creates a baser faerie, whose magic is heavily steeped in the element they are of. Celestial faeries are superb healers and oracles, often choosing to work in the human realm to aid those in need. The list of possibilities and the result are near endless.

4. Demon: Demons come from the dimension often labeled “Hell”, though it is more like an alternate realm where they live side by side with the human world. Unlike faerie, who can shift back and forth at will, they need to either form a tear to get through, or a powerful demon must form a halfway point so they can transverse between the two worlds with ease. Occasionally a tear forms on accident, often because too much negative energy pools into areas and rips the veil separating our world from theirs. No one knows much about them, except they harbor a hatred of humanity that is equal to and at odds with their fascination. Lower demons are often bestial creatures, some so horrible to look upon it is said that humankind cannot withstand the sight of them. High demons and greater demons can and often do pass as human easily, though only royal demons possess the precious curved horns that signify royal blood. No one knows when demons came about.

5. Djinn: Genies. Soul eaters. Are hunted the way demons are. Djinn come from the Middle East, and are thought to be corrupted faeries who must feed from the souls of those whose wishes they grant. There is also a popular theory that they are a group of faeries so vile and dark the faerie goddess cursed them to an eternity of misery and cast them from their rightful lands. Child faeries are often told that they will become djinn if they misbehave. Djinn are miserable creatures; they are just as twisted and maligned inside as out, often liking to drag out the process of feeding on a soul to draw out their victim’s misery. Once the soul is eaten, however, the husk is still alive, just blank. The djinn then implants just enough to it to pass as human and sends the animated husk out to bring in more food for them. Eventually the husk will wither to the point it is no longer useful, but it is so easily replaced it doesn’t matter. Djinn are gluttonous creatures that are never truly satiated.

6. Lycanthropes: cursed shapeshifters. They were people who were once human, but cursed to shapeshift into their totem animal.

7. Vampires: cursed beings. Once they die they rise again, bound to a geas that must be fulfilled should they wish eternal rest.

8. Shapeshifters: There are many kinds of shapeshifters, the most common being a family guardian. You can also have shapeshifter families, where the blood is passed on. In either case the animal is fixed, and typically based on the region the person (or person’s family) comes from. Some magi study for years to shapeshift, usually through the help of drugs, talismans, or something similar to help the body adapt to the actual act of changing shape. However, this takes a heavy toll on the body, as humans simply aren’t meant to shapeshift, and magi who follow this path often find trouble waiting for them.

9. Mer: People decended from waterpeople (mermaids). There are two kinds of mer; people who are half merfolk, and merpeople who are true decendants of the two races, neither one nor the other, just wholly themselves. They often live close to the sea; many are sailors or fishermen. Half merfolk often feel empty and alone, not belonging entirely to land, and unable to go to sea. Their saving grace is their very human lifespan, which ensures their misery won’t last forever. Merpeople however are immortal; eons of interbreeding amongst the two species have produced a new people, immortal like the merfolk, but landbound and unable to shift. They are powerful magi, however, able to summon storms as easily as quiet them, and command the sea like no other. Their power lies over the sea and storms, which make them invaluable to anyone oceanbound.

10. Merfolk: mermaids and mermen. Mermaids and mermen are not shapeshifters so much as possess the ability to shapeshift at certain times, such as the full and dark moon when they can assume human form for a few hours. Merfolk have an obsession with humans, beings who look so much like them but live on land that they often breed with them.

11. Elementia: people decended from elementals Elementia are highly unstable, but highly talented in the magical arts. They are often diagnosed as bipolar, or with borderline personality disorder. Powerful magi, they burn the candle at both ends, often dying early because their mortal shell simply gives out. However this usually produces a special elemental spirit, which while not as powerful as a pure elemental, is still a force to be reckoned with. There is actually a black market demand for elemental spirits because of their diversity of power and the unfortunate ease which they can be captured and/or bred. Elementia are probably the only people more sought after by demons than humans. Their fusing of human and elemental make them far more powerful as familiars, but they rarely survive the process to change their physiology because of how weak their bodies are. Rumors abound in the demon world about how to change an Elementia spirit into a familiar however.

12. Elementals: a race of people formed from the elements themselves. They are the least human, even more so than demons. They are rare indeed, as the elements and their power have to coalesce to form a new being. Because they are borne of the elements themselves they are utterly alien. However, they harbor a fascination with humanity that is matched by no other race, and they quite often father Elementia. They are the personification of their element, but much more condensed so therefore more potent. An elemental’s power far surpasses that of any other people, even the most power of demons because they are essentially crystallized elemental force.

13. Angel: Angels were the first race, but they don’t let it get to them (mostly). They rarely show themselves to the other races face to face, but the older ones often let themselves be worshipped as smaller gods and goddesses. They are renowned for their healing abilities, which surpass that of every other race.

14. Dragon: Don’t come to the human realm much, if at all, anymore. Dragons are the second race. Once upon a time they lived in the human lands, but created their own realm when humanity evolved. The sheer contradiction humans portray fascinate dragons. It was through careful breeding that dragonkin were born, meant to be protectors of both dragons and people alike.

15. Dragontouched: a person who is part human and part dragon. This is different from dragonkin because they are very much a cross of two races, not a created race of hybrids. Dragontouched are very intense, and it shows in everything they do. They are mortal, but live much longer than humans (averaging about 150-200 years). Their magic is chaotic and unpredictable, often causing strange side effects.

16. Human. Humans are basically just that, humans. They are quite versatile creatures, able to use many different things and forms. This is further aided by the presence of other races in the bloodline; humans are heavily influenced by the other races. They may not be immortal, or hardy, but they are flexible and versatile, and can breed with any of the other races.

Lycanthropy is a biological curse. To curse someone with lycanthropy requires a lot of anger and hatred. This negativity bleeds into the spell itself, so that when someone is afflicted, they can actually spread it to others if they are angry enough. The curse can be removed by someone skilled and strong enough, but there is usually strong backlash from it and there is only a small chance (around 1-2%) that the person’s mind will survive. Because it originated as a curse, there is no inoculation against it, and there is no medical “cure”.
The curse itself does not usually dictate what kind of animal it will form as lycanthropy often takes the form of the person’s totem, or animal spirit. Wolf is common because they are a common creature, and live mostly in packs. Out of the cats, lions are the most common because they live in prides. This is because man is a social creature and so most human’s totems are therefore one of the more social creatures. However, despite the totem usually being the creature a lycanthrope shapeshifts into, this is not always the case. Rarely is a prey animal seen and even rarer still, if it happens at all, is an animal smaller than a housecat; the possible exception to the size rule would be a bird of prey, though no very small hawks (like the kestrel, or sparrow hawk) have ever been reported.
Because it originated as a curse, there are some aspects of lycanthropy that aren’t true, despite superstition and legend. Silver affects them just like anyone else, though a blessed weapon, depending on what deity is invoked (if at all) may. They are stronger than humans, though not as strong as vampires or demons or even a natural shapeshifter. They heal faster than normal, but only instantly heal when shifting from one form to another. However, they heal so efficiently in either form they do not age. Their metabolism does speed up by a little bit, but no more than an athletic human’s, and so they are still affected by drugs and other such substances. Their senses do become sharper than normal because of how closely they are tied to the animal kingdom. Only some of them are tied to the full and new moons and forced to change though. Those known as Alphas are not tied to the lunar fluctuations, and can stay in either shape for as long as they choose (a normal lycanthrope cannot). These is because they are, for whatever reason, deeply bonded with their other half, and so reap certain benefits from this relationship. Because it is due to the bond between human and animal in a lycanthrope, some can actually become Alphas if they try hard enough. For others, it comes naturally. However most reject their other half, as they cannot come to terms with being so close to an animal in spirit and body so they never become Alpha.

These are all pretty good and well thought out.

What are you going to do with them? it would be nice to see some conflict within a race (an abberant demon who might do something good or a djinn that might act different from the others) within your story too.

My field of expertise is neurophysiology, so if there is a question or something feel free to ask.