A small group of ponys walked across the plains, near a river, heading north. They carried with them tents, food, seeds, and other things needed to survive. This, was a large number of the Crystal ponys. They all had the disease Crystolin. This disease gave them shimmering coats, like they where formed of liquid gems. Magic, like that of a unicorn, but less powerful, and none of them had horns or wings.
It was also deadly.
A non-Crystal pony who came into contact with a Crystal pony, would likely turn into a solid gem. A gene carried by the Crystal ponys protected them, but not others. They where shunned, hated, feared. So they left Equestria, so protect themselves, and others.
And they had found the perfect place. A long way away from other pony settlements, a river would allow them to water crops, a nearby forest could be torn down to make houses. One of the ponys in the front smiled, and yelled out to the others "We can camp here, start some crops." And they did. This, was the founding of a small, Crystal village. One that we would later know as, the Crystal Empire.
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A few generations later we find the little Crystal village thriving, well fed, larger, and happy. Their gem-like coats glistened in the sun, and sparked under the moon. No longer fearing other ponys, or being feared by them, they could live normal, pony lives.
Or so they thought.
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Duke Sombra smiled, as the last of his guests departed. He was considered very handsome, and was quite rich. He was quite ambitious, and hoped to one day rule a small kingdom. King Sombra. Wonderful name, he thought. In resent years, a vaccine was created, for immunity against Crystolin.
One of his guests was one of the very few remaining Crystal ponys in Equestria, which caused him to think about the times with Crystal ponys where feared. Where had they gone? Just 60 years ago a very large number had simply vanished. Now why would that be?
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A few years later, the Crystal ponys from the village look out with wonder. A unicorn was walking towards the village. He had with him a small group of soldiers. All, armed to the teeth.
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