Fun:Unicorn

According to the Paterson guide of supernatural entities, the unicorn (Monoceros gracilis) is one of the most shy and evasive (if not the most) creatures that roam the forests, at least in those very few spots where Nature has not been spoiled by humans in one way or in another.

Physical description
Originally unicorns were basically goats with just a single horn in the middle of the eyes. However as time went on they gained equine features and became larger until now when they're described as basically horses with a horn in the same place, something suggested to be the result of evolution as the unicorn has changed its looks following the changes on the tales about them. However travellers who have gone to distant places as Faerûn or Celestia among others claim that unicorns there have that horse-like look, so it's very possible those horse-like unicorns are (presumably illegal) aliens that have come here for whatever reasons and not the result of evolution.

Another change has been how the early-goat like look of them has been replaced with white, often plus corny, eye-searing rainbow colors, and a cute look (as this: 🦄) thought to be another result of evolution, this time to repel people who hate those things.

Hunting (figuratively or not) unicorns
Like dragons, unicorn's existence has ended being severely threatened by the advancement of both weapons and vision enhancing technology (infrared visors and cameras to be more exact). Not because killing an unicorn needs heavy firepower unless someone wants to go overkill (any rifle suitable for deer hunting should be OK, even if for those that use magic an anti-materiel rifle is recommended just in case), but like dragons because a skilled hunter can attack it from a much farther distance than using a bow, even one of those magical ones of supposedly elven manufacture, thus being safe of a charge by an unicorn using its horn as a lance, but also because said gear is able to bypass the magic they use to become invisible.

Photography, as most wildlife photographers are also behind unicorns to immortalize them on a picture and -just like phantoms and the like- as they appear in photographic gear either film or digital sensors, has ran a similar course especially given that film has mostly been replaced with digital cameras meaning that from the 24 or 36 opportunities someone had to hunt one a photographer can now have up to several hundred if not more (depending whether you shoot in RAW mode or not) without having to carry on a lot of film rolls and the appearance of superzoom cameras as well as long, (relatively) affordable, luminous telephoto lenses for SLR ones, has also helped photographers a lot. Something similar can be said of video recording, as now most digital cameras can record video too even giving professional results without having to carry around even heavier gear.

The result of the above, along with other toys as drones, remote-controlled cameras and the like, has been a race between unicorn's abilities, magic or not, to hide and human technology, with the former seemingly winning it as unicorn sightings have dropped considerably. Even the old tactic of using a virgin to tame one has ended failing, as there're no more fair, pure, maidens as in the good old medieval times (except if you were a peasant, that is), and the only unicorn that can be spotted in the wild, albeit with much effort especially if one is not an astronomer, is the constellation of Monoceros

Uses
In this modern world of medicine, pills that can purify water, and all that jazz, unicorn's magic -contained in its horn - has lost most of its former appeal, helping a lot that an unicorn's horn is indistinguishable of the one of a narwhal unless one uses DNA testing (and even in that case it has been reported to be just regular horse DNA, maybe another defensive tactics of those animals magical beasts).

What is still used are both its tears and/or its blood, used to elaborate drinks as those water or soft drinks bottles sold at vending machines, as well as theaters or other certain events where many people go as concerts and the like as well as high-end restaurants, this explaining why said products they're so expensive there.