Clearly Aedrides isn't populated solely by ponies, so if you have any ideas of what other sentient creatures live on the planet, or how other races such as the Griffons and Minotaurs have advanced after the storms, post them up here. Just remember that there are very few real governments left these days, with most of the world being carved into small city states, or controlled by small time warlords or bandits.

All right then, let's see what I can tag.

Pony - The main race present in Equestria, they're generally social and generally vegetarian, though ponies can probably eat some meat they can't process it as well as plants. All sub-species of pony are intelligent and flexible, however they each have unique traits:
Earth ponies - the 'normal' pony, they've a great connection to the earth and often said to use their magic to enhance either themselves or the things they make/grow.
Unicorns - general spell casters, obvious due to their horns, which, if damaged or corrupted, renders them unable to use magic. Most are capable of telekinesis and spells related to their cutie mark
Pegasi - winged ponies that are capable of weather manipulation and cloud walking, they basically control the skies
Crystal - A variant of earth pony that looks like it's made out of crystal rather than flesh
Thestral - Nocturnal variants of pegasi, these ponies have bat-like wings instead of bird-like, they also have pointed fangs and slit-pupils, the latter allowing better night vision than most, the former suggesting they either eat more meat or they drink something, possibly blood, more likely some kind of sap or insect
Changeling - Fanged and shelled, these beings look like insectile unicorns for the most part, though they feed on emotional energy. They are capable of producing some form of resin that can be used to cocoon others and had their own queens before the storms
Alicorn - A mix of the first three species, only four are known. Celestia, who controlled the sun until the storms, Luna and Twilight, both listed as missing, and Cadence who ruled the Crystal Empire from its re-emergence to the storms and possibly rules there still. Alicorns are generally seen as the pinnacle of the ponies, capable of magic and speed beyond the norm.

Horses - Similar to, but taller than ponies, they used to mostly live in the Saddle Arabian deserts.

Zebra - Pony sized, but striped in black and white or grey, they mostly live in the savannahs to the south, with a rare few living in Equestria. At least until the storms hit. They are capable of alchemy and possibly other magics related to crafting, similar to earth ponies with their growing or making enhancements.

Gryphons - half cat and half bird, there are a number of variations of the gryphon, most of which prefer mountain aeries or clouds to the ground. Most are also more inclined towards meat, though they often don't eat it as much around ponies, possibly more due to inability to get it than lack of want for it. Their talons are a lot more dexterous than hooves, but there has been no sign of magic beyond that used by pegasi from gryphons.

Minotaurs - Upright bipedal creatures with ape-like torsos and cow like legs and heads. Like gryphons, minotaurs rely more on manual dexterity than magical power to get things done, though they are fairly strong. If any native race can readily adapt to technology brought in by bipedal aliens, it is the minotaurs.

Buffalo - large nomadic bovine creatures, they prefer moving around plains and desert over settling in one place, though some trade with ponies for food.

Cows - bovines often protected by ponies in return for milk that can be turned into diary products, they don't seem inclined to try anything, though they are easily spooked at times and tend to stampede when that happens.

Donkeys - another equid race, they're notable mostly due to their larger than normal ears, longer muzzles and stubborn temperaments

Diamond dogs - Canids that, like minotaurs, are built upright and capable of handling biped tech, if they can figure out how to use it without someone standing next to them all the time. Most of the known diamond dogs are either focused on gems or less than bright.

Sea serpent - Related to dragons, sea serpents spend most of their time in water. They're intelligent and capable of handling themselves, though their long bodies and need for water limits their interactions with other creatures.

Dragons - The largest beings known to possess intelligence, dragons are frightening foes if you don't have either vehicles or heavy weapons as they can fly, spit fire or other things and have their own magics. Most also weigh in at over five tonnes in mass, some as high as fifty. While they're unlikely to be bothered by most of the new creatures, they do like shiny things, and are inclined to take things they like the look of by force in order to improve their hoard. Most are solitary once they reach adulthood.

Humans - not native to Aedrides, humans are probably the most common sapient ape, and also one of the ones most likely to adapt to its environment, either through magic or technology. While some of the humans have less tech than the sea serpents or dragons, others have built ways to travel at speeds faster than light itself, and explored the galaxy. While many are easy kills, you do not want to underestimate humans. If you do, they will make you regret it.

That'll work for a jumping off point.

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Thought I'd add a few non-canonical species:

Equinox Novus
One of the more intelligent species creatures to now occupy Aedrides, the Equinox Novus are some form of ponykind, improved beyond the species that held dominion of Aedrides before. Whether they were ponies that had their evolutionary tract accelerated by the storms, or if they have been deposited on the planet from some alternate future, one thing holds true. They are bigger, faster, stronger and smarter than ponies, superior in almost every way. They have used this superiority to carve out large swathes of land as their own, forming one of the few coherent governments left on the planet.
That being said, they Equinox Novus, or simply ‘the Novus’ do not go out of their way to seek hostilities with the other races, and are more than happy to trade to get what they need or want. They are not pushovers however, and if pressed they will mercilessly hunt down their aggressors. It is the defining trait of the Novus that once a cause has been taken up, no force in existence will cause them to deviate from it, be this friendship, the hunt, or war.

Skaven
A lesser race on Aedrides before the storms hit, the majority of the world’s inhabitants didn’t even know of their subterranean existence, just as the skaven were largely unaware that there were creatures living above them. That all changed when a large storm ripped the capital city of the skaven from two miles beneath the planets crust, depositing it outside a pony settlement. Dazed and confused, the skaven and the ponies quickly came to blows in a conflict that exposed the skaven existence to the world.
The skaven are not particularly threatening on their own, each one being roughly the size of a filly at their highest height upon their two legs. Even their kings are not much of a threat to careful travellers, and one may be forgiven for thinking that the skaven are not a threat. Those that think that however are most certainly wrong. Dead wrong
Skaven are never alone, and where one is, another hundred will surely follow. The only thing that matches their numbers is the savage cunning each skaven bears with it. When put to the pursuit of war, goblins will use every weapon at the disposal, be they pony swords, crude weapons that they have made themselves or even weapons stolen from some of the travellers if they can get their thieving hands upon them. If a horde of skaven is approaching, it is already too late for most creatures. You can run, and be caught, dragged off to their underground layers for who knows what, you can surrender, and meet with a similar fate, or you can fight, and pray that they don’t take you alive.

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Not sure I'd personally have put Goblins in as natives myself, they don't seem to match with the rest of the general mix canon gives us, in part because they're generally not particularly animal like. I probably would have gone for kobolds (small lizard folk) over goblins.

4124446
Changed to rat-kin

4126937 Cool

Right, this post is focused on beings from my original universe so they're among the rarer ones on Aedrides, most of them either ending up there due to the storms or the aftermath, it also gives some indication of what things are like in regards to the group Spitfire and the others encounter in that universe.

Hreathrae

Hreathryn (hreathrae) is the collective name for the five known bipedal dragon subspecies in the Dforgrym-verse. As a group, they are actually a descendant species, though no-one living knows what their forebears actually were called, only that at some point in the past they sent out several massive transports to take life to other worlds before being wiped out. Of those worlds, only five have been found, it is likely that the rest of the twenty transports were destroyed en route.

All dragons of this type are upright bipeds covered in scales, with wings and tails at their backs, and all have the ability to communicate telepathically with one another. They generally stand around 8 foot 6 inches to 9 foot 6 inches in height, though the rare 'midgets' can be as short as 6 feet tall while the 'giants' amongst them can get up to 12 feet.

They also all share the ability to alter their form, with certain cavats. The most common one being the fact that they need to gain a sample of another creature's DNA in order to make a form, the other being the amount of energy it uses. The larger the difference in mass between forms, the harder it is to change into one, except reverting to base form. Because of this, even though the retrovirus originally used to seed the five groups can create a viable change, there will often be 'bits' of the base forms visible, or of the 'base dragon' if someone is changed into one and gains the ability to shape shift from sharing blood with them. Magic cannot replicate this particular virus, even though the virus itself allows the use of magic in certain ways.

Franthoryn (franthryn/franthrae) - The group with the most in common with the standard 'western' dragons, their homeworld is the planet Harrenthias, and they generally have a single pair of bat-like wings, feather-scale crests and nobles are often glossier scaled than their common-born counterparts. Most of the time the franthryn track lineage by name, usually in the form of {name} Mac/nir {parent's name} of {place}, generally the females use nir and then their mother's name, males are mac and their father's name. The place is their place of residence. Royal clans, however, have a clan name which all children of the clan have.

Rhyl'saar(ii) - Born of a system that has two inhabited planets, the rhyl'saarii are marked different from their cousins primarily due to the fact that every one of them has a mane. They also tend to be the youngest to experience heat, often at around the age of ten, two years prior to shedding their child scales and gaining their adult ones, along with the more armoured appearance and scale ridges along their arms. However, while they encounter heat earlier than most, they can't actively breed until they are near twenty, a similar age to their kin. Nobles amongst the rhyl'saarii are marked with pure black scales across their bodies and a coloured mane, usually indicative of their clan. Of them, two in sixty-four 'nobles' are 'royal', bearing both four wings and a set of horns on their face, the others are roughly evenly split between having the extra pair of wings and the facial horns.

Ailiaar - Unlike the others, ailiaar actually have feathered wings, more along the lines of birds than bats, and are often considered among the better fliers of the group, though none are bad as a group. While the rhyl'saar and franthryn home worlds tend towards monarchies and tech levels around the medieval period – bar certain relics such as weapons, armour or computers – the ailiaar were closer to the age of gunpowder in Earth's tech time line, at least before they found their seeder ship and met with the other groups. Also unlike the others, there is no obvious way to tell the 'nobles' from the 'commoners' as all have a pair of feathered wings and feathers forming a 'mane' and 'ears' for them.

Tregun - water dwelling dragons, almost all tregun are partially amphibious, with much higher pressure tolerance and gilled throats allowing them to build under water. Also unlike the others, their wings are designed to move in water rather than air, meaning they are poorer fliers than most, but their streamlined bodies, broad tails and webbed digits enable much more manoeuvrability underwater.

N'krondii - This group, once again, is different from their counterparts, not due to the fact they dwell in a world where there is more water than land, but due to the fact that, while, like the rhyl'saarii, they are live born, unlike their counterparts, they don't have any form of wing until they hit their adolescence, something that happens around about their twentieth year, it is at this point that their wings grow in.

Rentaarii

The second sapient race sharing the system with the rhyl'saarii, they have their own planet and, for the most part look like bipedal unicorns. They are, however, not currently space capable and while their world is protected by the Dforgrym, the Hren Republic's space military group, they are not a part of it themselves, instead they tend towards medical practices or working with nature, preserving it. It is possible that had the Equestrians ended up on the planet Renataar, they would have become rentaarii rather than taken the form of hreathryn subspecies.

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The Changelings were one of the few cultures to survive the storms relatively intact, and certainly the largest. The old Changeling Alliance covered a few hundred square miles of wasteland, split into six main hives, nowadays, the Changeling Empire covers five times that amount, with three times as many hives. This is largely due to their Empress, Chrysalis.

Each Changeling is a marvel of biology and evolution, capable of feeding itself on the emotions of others if physical nourishment is not avaliable. While love is the most potent food source, any emotion can in theory be used, and it will slowly begin to influence the Changeling feeding upon it. For example, a Changeling gorged on hatred will in turn be bitter itself, as well as being stronger and tougher than a Changeling who has fed only on happiness. It is possible for feeding to be done of a subjects free will, but more often than not it is done on unwilling captives, cocooned in a resin secreted by the Changelings, and kept as a living food source, viewed as just another asset of the hive, to be used and expended at will.

Changelings are not however autonomous, and each one is slaved to the hivemind, which is now exclusively directed by Empress Chrysalis. A drone has no will of it's own, while soldier and brute classes may be given limited free will to better adapt to battlefield conditions. Even the command class has only enough free will to make them useful, but never enough to make them a threat to the leader of the hive.

Aside from this, Changelings are deadly opponents. Armed with magic and fangs, armoured with a natural exoskeleton rivalling pre-storm armour, and gifted with the power of flight, they are a force to be reckoned with.