when you think about it a unicorn is probably one the most realistic mythical creatures that exist (or in this case don't), no doubt people thought they existed for decades
AHEMHEMHEM-
Actually you'd be correct! For a lot of years, explorers believed that the Arabian Oryx were unicorns, as from the side it appears to have just one horn. Some theorize that the Okapi was possibly also thought to be a unicorn, since in many old depictions unicorns are portrayed as a mishmash of different horse-like animals, similar to the real life Okapi.
This has been supernatural animal facts with Overlord.
so i saw the oryx, and honestly i'm surprised at how people didn't thought it was a satanic creature, and what i'm even more surprised is at how nature hasn't been able to pull off an unicorn at this point, like goddamnit nature you creatured freaking dinosaurs but can't figure out a simple horse with a horn, what a shame