A resurrected species of supernaturals who are shape-shifters with the ability to change into a cougar. The species was brought back by Project Phoenix , along with 3 other extinct races. There are currently 4 known skin-walkers, 2 pairs of siblings, all teenagers. The experiment involved a group of mothers who wanted their children to be skin-walkers and not feel the absence of the shifts, as mentioned by Ash in The Rising. As there was a group, there are probably more skin-walker teenagers, but it is unknown as to whether their powers developed or not, or where they are.
All skinwalkers are born with a birthmark of a paw print. Girls' birthmarks are on their hips, and boys' birthmarks are on their shoulder. The birthmark remains as a colored patch of fur, like a paw print, when they shift into a cougar, and is found in the same spot as when they are human. This is to tell apart a skin-walker from any other cougar. So far, girls tend to shift before boys do, as it is seen between Maya and Ash. They are both twins, but Maya began shifting about 6 months before her brother.
Skin-walkers are from Native stories and folklore. Possibly the best documented skinwalker beliefs are those relating to the Navajo Nation yee naaldlooshii, literally "with it, he goes on all fours" in the Navajo language. A yee naaldlooshii is one of several varieties of Navajo witch, they had the ability to turn into bears, wolves, and coyotes and where considered to be witches. They were hunted until the skinwalker gene began to disappear, their children being born without the ability to shift. Anyone with the gene, but without the ability, felt the absence of the Shift, like something was missing. There are mostly references of them turning into canine creatures, and Maya manages to only find one mention of them turning into cougars.
Skin-walkers' main ability is to shift into a cougar. When they are in their human form, they have enhanced hearing and sense of smell, as well as night vision.They also possess a certain control over animals, and healing abilities, able to heal others, as well as healing themselves in some cases. Maya also has visions from other animal's points of view in The Gathering and The Calling. It is unknown if this is an ability that all skin-walkers posses or if it is just something she can do, as it is not mentioned in the third book, or when their abilities are listed.