A long time ago, on a world not so different from our own, the seas and lands were populated with spirits. See, in that universe, things work differently. Where we have science and electricity, they had the use of magic. Of course, magic has its own rules - and one such was that it is very hard to maintain a form for longer than a few months or years if you are incorporeal. After that time, you tend to drift apart, thinning like steam until you no longer exist.
The spirits lasted long enough to reproduce, of course. They wouldn't have been around so long otherwise. But after a few thousand years, they began desperately searching for a way to extend their lifespan. It's difficult for an intelligent society to develop when the individuals don't survive long enough to test theories or experiment in the magical arts.
On their world - Ateria
(Ay-TEER-ee-ah) - no physical creature had ever been discovered to have more intelligence than a dog. The spirits thought it wasn't even possible for a physical form to hold a greater intelligence, and so for hundreds of years, their efforts focused on finding ways to hold their essence together for longer periods of time. Failure after failure, decade after decade - until an experiment went terribly wrong, and it became almost impossible to retain their form. Throughout Ateria, spirits' lives were suddenly measured in weeks. It seemed to be the end.
In desperation, one young spirit, only days old - later known as Felewia
(Fuh-LOO-ee-ah) - came to the conclusion that any existence was better than none at all. And so he began focusing all his energies, his life essence, his very being, on a physical form. It had to be large, to contain (hopefully) a modicum of his intelligence. It had to be fast - Felewia loved speeding over the plains, and did not wish to give that up if he didn't need to. It needed to be able to protect itself from wild animals, if it could not escape them. And let's be honest, it needed an appealing form, or who else would join him?
Felewia grew brighter and brighter, until his small form could be seen from miles away. Other spirits gathered, first wondering what he was doing, then waiting to see the result - for if he was successful, they all would follow suit. Still glowing, the young spirit rose in the air until he was above the treetops at the edge of the forest - and suddenly the light went out. The spirits murmured sadly, believing Felewia to have failed, when suddenly a bright flash lit the sky - and Felewia slowly landed in his new form.
The spirits stared in shock. This was like no creature they had ever seen before. Felewia's new body was equine, for sure - but no equine had ever been like this! Wings of glorious feathers arched over his back, and a shining spiraled horn leapt from his forehead. His coloring, rather than some sensible shade of brown or gray, was as brilliant blue as the sky. And, most important of all, intelligence shone from his eyes.
The spirits rushed to duplicate Felewia's feat. Each had a slightly different picture in their mind, so many different forms resulted - all equine, but some had no wings, or no horn, or had scales instead of fur. Some had bat wings or fangs, some were more suited for the streams and rivers than the plains Felewia so loved. Thousands of horses of all shapes and sizes, each stranger than the last, filled the area for miles. As each took form, they'd pause for a moment, getting used to their new body, then bolt for whatever region suited them best. So it was that they grouped by type, spread throughout their world, and began life anew - with the longer lifespans they'd desired for so long.
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Thousands of years later, the spirits no longer remembered their origins, except in the old tales told by their elders. Having forgotten their common ancestors, the equine races often fight amongst each other, fearing the unknown or different. Our story begins with a herd known as the Tola. The plains they call home are vast; they haven't needed anything they could not find or make for hundreds of years. Their herd is vast enough that they haven't been threatened by another in a similar length of time. But the seers warn of trouble coming, a storm of war on the horizon....