Wechuge

Wechuge is a cannibalistic monster from the Athabaskan people from Canada and  Northwest American folklore. The Wechuge represents someone who has been cursed. They are born from the cursed souls of humans who have engaged in severe cultural taboos and become "too strong" - allowing ancient spirits of giant animals to possess them and transform them into large monsters made of ice. Often these beasts are the result of someone who craved the power of a great spirit animal, but could not control it and was turned into a Wechuge as punishment.

They are also considered very intelligent and cunning creatures who plan 
out their hunt and may even engage in trapping their victim. They are also a shape-shifting entity, though they tend to be depicted as large ice-monsters. In some tales they have large wings and in others they are half-human, half-animal hybrids.

A person can become a Wechuge by becoming "too strong" and being possessed by a giant spirit animal. This can result from breaking certain cultural taboos, like eating contaminated meat or having one's photograph taken without consent.

Other ways of becoming Wechuge include breaking societal taboos. These range from eating meat contaminated by fly eggs to having your photograph taken with the flash on. Thankfully, in the time of smartphones, you might be able to avoid that one but perhaps refrain from taking any selfies at night.

Wechuge can appear as normal animals - perhaps a representation of the spirit animal they were attempting to utilise - or as a creature made entirely of ice. If the creature is in its ice form, it can be defeated by throwing or pushing it onto a campfire, which should make short work of it.