What is Windigo?

The concept of a human turning windigo is symbolic of when a human has broken a long-held taboo and has unleashed an evil within them that they can never come back from. Even though their present environments may have caused them to do something unspeakable, the windigos had a choice not to act in the way they did. It is seen in all three of the instances where a windigo is killed. They all feel remorse and do not want to die but they cannot come back from the dark place they have traveled to.