The concept of the skin-walker is unique to the Navajo people. In their language, the word yee naaldlooshii means, "with it [the animal skin], he goes on all fours."
Skin-walkers are associated with trickster animals like the coyote or with animals representing death and bad luck.
They can turn into any animal they want by wearing its skin.
A person becomes a skin-walker by killing someone in their family.
Skin-walkers can be killed by bullets dipped in white ash.
However, these bullets won't work unless they hit the skin-walker in the head or neck.