Skinwalkers

are supernatural creatures that transform into animals. They can shift from human form into dog form whenever they want. They much like werewolves they eat heart.

They are said to be the cousins of werewolves, due to their similarities. But they can change at any time instead of being limited by the phases of the moon. Also, their transformation into an animal is complete, whereas werewolves continue to walk upright.

Numerous cultures all over the world believe in some version of a Skinwalker, which is closely related to beliefs about werewolves and other were-creatures. The best documented Skinwalker beliefs are those of the Navajo yenaldooshi. The yenaldooshi are evil human beings who have gained supernatural power by murdering a close relative. The creature travels by night, spreading misery and desecrating holy things. He or she is usually naked, except for a coyote skin. The yenaldooshi is also said to have the power to assume the form of a coyote or other animal.
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In Norse folklore, a Skinwalker is a person who can travel in the shape of an animal or take on certain characteristics of an animal. The most well-known example is a warrior who takes on the strength and stamina of a bear, called bear shirt or berserker.
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Know Powers & Abilities
Infect others with a bite (just like Werewolves) -> topic id: 2775194
Transformation Skinwalkers transform back and forth from human form and dog form whenever they want. Unlike their cousins, the werewolves they have complete control of their actions when are transformed and do not depend on the lunar cycle to transform. They usually tranform into a dog to escape.
Enhanced Smelling They can smell a scent far better than a human. Using this ability they could tell if they are being followed. They could use this ability in either form.
Accelerated Healing They appear to be able to heal themselves faster than humans.
Enhanced Strength Thier strength seems to greater then the average human.

Weakness
A silver bullet can kill a skinwalker if they are shot in a fatal place. It can also be used to bind someone, a rope or chain wrapped with silver.
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Of course there is, an Alpha Skinwalker, but I have not much information of it. Except it's the father of all skinwalkers