whoaaa whoops this was not supposed to be this detailed but I'm okay with it tbh. Watch out guys. It's your boi, Prometheus, and he's about to harmonize your sorry asses.
Prometheus was the first alicorn, a fallen form of a forgotten race of beings known as Omnicorns. Upon bestowing magic in the ponies of Equestria, he disrupted the balance of life forever for all good forces in this world are accompanied by the bad. As punishment for his carelessness, his godhood was stripped from him, and he and his followers were forced down to the earth to live a mere 10,000 years as alicorns. For truly immortal beings, 10,000 years is a blink of an eye in the 14 billion year lifespan of the universe.
Although Prometheus desperately wanted to help the ponies, teach them the ways of the Omnicorns, the godlike beings forbade it and threatened the extinction of ponykind if he attempted to meddle in their affairs ever again.
For generations the alicorns lived sequestered atop a towering peak. As was their wont, it was always spring upon their mountaintop, and they surrounded their humble village with a roaring storm to keep wayward ponies away. However, as a favor to the ponies below, they controlled the elements for millennia, moving the sun and moon, changing the seasons, optimizing plant growth with their sheer magical ability. The ponies came to revere them as gods, and so worshiped them.
The alicorns gave the ponies faith in their dangerous world, and forever they would pray they would come down from Tempest Mountain and bring paradise with them.
Such would never be the case, however. Erebus would see to that.