As the Fae settled into Allutheria and realized their unlimited potential for shaping this world, they realized how critical it would be to ensure the balance was not upset. Since it would be impossible to track every Fae and monitor their magic usage, a group of Fae sought to create a race of guardians who would act as anchors for their world. The Horned King was recruited with some coercing to aid them in their creation process for how he had been critical in forging the Black Cauldron, a power augmenter unlike which Ga'leah had ever seen. For Allutheria, however, they wished to create the opposite. Thus, the unicorns were created as nulls.
The Fae thought it was too dangerous to allow their new creations the full spectrum of emotion, having experienced firsthand how emotion easily led to rebellion and conflicting loyalties. Not wishing to see their new creations fall prey to any Fae who sought a null army, these Fae bound the emotions of their creations and cultivated a distrust for Fae. Every magic comes with a price, and a curse cannot be set without a key. The key to unlock the curse of absence of emotion differed from unicorn to unicorn. Each unicorn had been given a name upon creation, a name they would never hear for the moment they heard it, they would unlock their true potential and truly be immune to all Fae magic.
A finite amount of unicorns were created and stationed across Allutheria to serve as guardians over their plot of land. Not trusting the words of his fellow Unicorn creators that their identities would be kept secret from the Unicorns and other Fae, the Horned King killed them and took all the names of the Unicorns for himself. Although the Unicorns do not know him by name, they are familiar with his presence. They do not bow to him and are not drawn to him as they are to pure individuals, but it is rumored they are more likely to listen to him than the average Fae. Perhaps it is their intuition that knows he holds the key to set them free.
They are solitary creatures. Though they seek the companionship of nearby Fae and animals, they do not feel any drive to mingle with others of their kind. Most never stray from the part of Allutheria in which they were first placed.
Unicorns are equine creatures with the cloven hooves of a goat, the tail of a lion, and a slender, spiraled horn on their forehead. They are slightly smaller than a Quarter Horse and more lean along the barrel and flank of their bodies. To most people without magic ability, a unicorn will appear as nothing more than a white horse. Some with a deep seated desire to see a unicorn can retain the ability to detect them through sheer act of will alone.
Unicorns are incapable of reproduction. They lack true gender and are therefore completely sterile. During their creation process, it was decided by their creators to bind their capacity for emotion. While they are capable of anger, aggression, fear, contentment, and sorrow, they are not able to feel love, hope or regret.
Unicorns are nulls. Magic, except that done by the gods, has no affect on them. The Fae and Half-Fae are typically incapable of creating an enchantment that can affect an unicorn. By the same rules, a unicorn is incapable of working magic themselves. Instead, they use their nullifying abilities to end curses, heal magical poisons, stop enchantments, and much more.
Unicorns, if left undisturbed, are immortal and will never perish from old age. However, they can be killed through physical means if a non-magical injury is acquired. Serious injuries would be fatal, even to the immortal unicorn. Unicorns also have a weakness for the pure of heart or spirit. They are inexplicably drawn to them.