A skin-walker is a legendary creature in certain Native American cultures that is somewhat analogous to the European werewolf. Like the werewolf, it is a shape-shifter, human at times, and at other times taking on the aspect of an animal, usually at night. In its animal form, the creature may be virtually anything, including a wolf, coyote, fox, bear, owl, or crow. Although skin-walkers may have a favorite form that they customarily use, they have the power to become anything they wish. While the creature is known mainly from Navajo folklore, analogies exist in the mythology of other tribes, including the Mohawk, Hopi, and Aztecs.
In the Navajo tradition, the skin-walker or yee naaldlooshii is a human who has gained his or her powers through witchcraft. They are frightening, dangerous, and difficult to kill. Witches earn their power through violating a taboo and generally use it to harm others, so they are considered a sort of monster.
In animal form, a skin-walker is very fast and impossible to catch. It sometimes transform itself into animals simply for the purpose of traversing great distances quickly. These creatures may also transform in order to wreak havoc on others, as their identity will be hidden and they will be able to escape quickly if necessary. Both humans and animals can easily tell a skin-walker from a real animal, as it is unable to move completely naturally in animal form.
A skin-walker typically wears the pelt of the animal he or she will transform into, usually with no other clothing. Because of their association with such creatures, wild animal hides are taboo in Navajo culture and rarely seen. A skin-walker can only be defeated if one can discover his or her human identity. This is possible if it is tracked back to his or her home, or, in some stories, if one is wounded and the same injury is later noted on a human.
While it is virtually impossible to kill a skin-walker in human form, there are magical ways to protect oneself and even to kill it. Traditional faith healers can perform ceremonies to protect people from the danger of the creature, or a person going out at night can cover his or her body with corn pollen, cedar ash, or juniper berries. If a person discovers the creature's human identity, he or she can kill the witch by saying, "[Name], you are a skin-walker."