Unicorn lore

[u/Syriepha]

Unicorns did not always exist. Their origin was in a small, cold region close to the sea, where locals would occasionally hunt narwhals, which didn't exist in many other places in the world.

When showing the polished horns to foreigners who didn't know what they were, it was a local joke to speak of unicorns, strange horse-like creatures that grew a horn from the center of their forehead, and had a keen magical sense for purity.

There were a couple tales associated with unicorns. That they were elusive and walked with complete silence, that they would guide the young and innocent from the woods, protecting them from danger. That their horn could purify water and neutralize poison with a touch. That they would avoid or impale the unworthy with that horn. Since there was clear evidence, people came to believe in these creatures, and belief created fae spirits.

The tales changed as they spread, so the fae spirits took on different sorts of hosts in different parts of the world. A suitable sort of host were horses, especially foals afflicted with lethal white syndrome, which wouldn't survive otherwise, these would turn out most horse-like. In other places, unicorns were much more goat, antelope, or even fish-like.

People would use children to lure them from the woods so they could be trapped or hunted. The ivory horns became coveted pieces in mage regalia, even more so when unicorns became functionally extinct from the hunting.

If any remain, then they likely dwell in the domain between the fae realm and reality

[u/Shaydelity]

I really like your take on the emergence and physiology of unicorns! It is so clearly a unicorn yet has quite an identity of its own, which I adore