What is a wendigo in Supernatural?

What turns a person into a wendigo in the show?

Eating other people. In the show's rules a wendigo starts as a human being who ate human flesh to survive, often when cut off and starving in a hard winter, and the act changes them into a creature that keeps the hunger and loses almost everything else. What is left is stronger and faster than any person, can live for centuries, and wants nothing but the next meal. Little of the person survives the change.

That origin is what made it such a good early monster for the series. It is frightening, but it is also sad, because the thing in the woods was a person once. A great deal of the first season runs on monsters with that kind of human root, creatures made by grief, anger or one terrible choice, and the wendigo set the tone for the hunts that came after it.

Why does fire kill it when other weapons fail?

Because the show gives most of its monsters one decisive weakness, and the wendigo's is heat. Bullets and blades only irritate it, so hunters have to work out how to get close enough, or lure it near enough, to burn it. In its first episode the answer is a flare gun, an improvised weapon that suits the show's working idea of hunting: carry what you can, and know exactly what each thing in the bag is for.

Fire also gave the case a clear endgame, and early Supernatural depended on clear endgames. Each hunt had to establish its creature, its rule and its limit inside a single hour, and one weakness made that possible. The show's lore does allow a slower and far more gruesome method involving silver, but fire stays the answer the series reaches for, simple to state and hard to carry out.

How does a wendigo hunt, and how do you keep it out?

Like a patient predator. A wendigo can copy human voices, so a call for help in the dark may be the creature itself, and it moves faster than anyone can run. It does not always kill at once, either: it keeps its prey alive in some dark, out-of-the-way place to feed on later. Between feeds it sleeps for years, which is how the first one could strike Blackwater Ridge every 23 years and leave the place quiet in between.

What it cannot do is cross Anasazi symbols. Laid out in a ring on the ground, they stop a wendigo at the line without hurting it, which makes them a shelter rather than a weapon. The distinction matters in the show's craft: hunters carry some tools that kill, some that protect and some that only slow a monster down, and knowing which is which is most of the job.

How did the series build its second-episode monster?

Around its human past. The season 1 production history records that the creature was given human features because it had once been human, and the ability to imitate voices purely because it made the hunt creepier. The show's creator was not happy with how the finished creature looked, so it stays out of sight for most of its episode, which turned a limitation into slow dread. Its burning was hard to film, too, and needed a second attempt with a burning figure added afterwards.

As the monster of the second episode, first shown in 2005, it is one of the first two creatures the show ever built an hour around, and many of the series' habits are already in place: a remote setting, a creature with one decisive weakness, a rule the brothers learn under pressure. The mythology grew far larger later, but that model of a self-contained hunt never left the show.