Anuk-Ite

Anuk-Ite is a supernatural entity released from the Wild Hunt after Scott McCall's Pack saved Stiles Stilinski from the Ghost Riders in Teen Wolf Season 6.

Teen Wolf Myth
The Anuk-Ite entity appears to be invisible except when it infests people and animals via burrowing spiders. It has also appeared as a faceless, bloody, humanoid-shaped lump of skinless flesh. Medical tests performed by Melissa McCall showed this incarnation of the creature has no DNA or cell structure. While visible and tactile, it does not exist in any measurable sense.

Dr. Deaton explains that “It is an ancient shapeshifter, a creature of disharmony. It can turn neighbor against neighbor sowing the seeds of discord and hate. It doesn’t need fangs. It doesn’t need claws. It uses something far more sinister. When paranoia turns to anger, anger turns to violence, entire communities tear themselves apart. The creature feeds off the fear and grows more powerful.”

The hellhound Halwyn apparently locked it away in the Wild Hunt in prior to 1912 and then locked himself away in Eichin House in case the creature ever returned.

Real Wolf Myth
Anuk Ite is a common myth among Native American tribes. It is known by many different names but all of them tell a tale of a creature with two faces that delights in tormenting people.