Everyone knows Santa has a naughty list and a nice list, but generally speaking landing on the naughty list really isn’t that big of a deal. Instead of a present, legend says a kid gets a lump of coal. A day ruiner, sure, but not a life ruiner.

Landing on Krampus’ naughty list, though, is a much bigger deal. He’s the titular star of the new horror movie Krampus, about a family who loses sight of the Christmas spirit and in turn inadvertently discovers Santa Claus basically has an evil twin.

So is Krampus a real thing?

Yes. Well, that is to say he’s as real as Saint Nicholas. Hailing from European folklore that is hundreds of years old, Krampus is basically the bizzaro Santa Claus. He only gives out punishment, never presents. He’s also neither fat nor jolly, he’s creepy and has devil horns.

In some European traditions, particularly those in and around the Alps, Krampus goes hand in hand with Saint Nicolas for one simple reason. In that version of the folklore, Saint Nicholas exclusively gives out presents while Krampus exists to deal out holiday justice to those little kiddies who have misbehaved.

And people do actually celebrate Krampus as a holiday figure. In Austria, for example, Krampusnacht (Krampus Night) gives the baddie a night all to himself on the day before the Feast of St. Nicholas, when people dress as him and walk in parades. In other celebrations, Saint Nicholas and Krampus parade around the streets together. He’s all over greeting cards and advertisements. There’s even a thing called a Krampuslauf where a bunch of adults put on Krampus masks and run around drinking schnapps.

Does Krampus actually torture people?

No, not in the folklore. He’s a jerk, but he’s not a murderer. He gives bad kids coal, but unlike Santa in American culture, Krampus goes one step further. In addition to the lump of fossil fuel, he gives them a bundle of sticks that they then have to display in their house as a constant reminder that they got burned by Krampus on Christmas.

But watching kids get shamed by receiving the “ruten bundle” would make for a pretty dull horror movie, so you can count on Krampus writer-director Michael Dougherty to dial up the scary factor with some ideas that you probably won’t find in 15th-century legends.

Are there other movies with Krampus?

There’s been a bit of a boom in Krampus-related movies lately. Krampus is both the highest profile production so far and the best of the recent bunch, but it’s not the only one. The straight-to-video front this year has already given us A Christmas Horror Story (read our interview with the movie's star William Shatner), Krampus: The Reckoning, and Krampus: The Christmas Devil.

Why the sudden wave of Krampus fever? You can probably thank the fantastic 2010 horror movie Rare Exports: A Christmas Tale, about a family who tries to trap and sell Santa Claus only to discover the real Santa isn't quite so nice. The funny thing is that Krampus isn’t technically even in it -- they sort of just roll the Krampus-ness of Krampus into their version of Santa Claus -- but it did introduce a lot of non-European audiences to the fact that Saint Nicholas folklore does have an actual dark side to explore.

Krampus hits theaters on December 4, 2015. It stars Adam Scott, Toni Collette, David Koechner, Allison Tolman, Emjay Anthony and a very, very angry Krampus.