A widespread legend is that, when Noah gathered two of every kind of animal, he neglected to gather the unicorns, which is why they do not exist today.
The unicorn is a legendary creature like a horse, but with a slender, usually spiral, horn growing out of its forehead. The popular image of the unicorn is that of a white horse differing only in the horn.
In medieval lore, the spiraled horn of the unicorn, was called the alicorn, and was thought to neutralize poisons. In popular mythology, unicorns were hunted for their horns, which were said to protect one against diseases, or, if made into a cup, would protect on eform any poison that might have been added to one’s drink. This belief is derived from Ctesias’ reports on the unicorn in India, where it was used by the rulers of that place for anti-toxin purposes so as to avoid assassination.