"Krampus" is an excellent and fairly fresh alternative to cute romantic films about Christmas, where in the end everyone finds happiness and one big family gathers at the table, like in Coca-Cola commercials. This is a scary Christmas tale that can easily scare a child and, perhaps, slightly amuse an adult.
A bit of history. According to Alpine folklore, Krampus is a goat-like mythical figure, a kind of antipode to Santa Claus, who turns up to naughty children, punishing them for bad behavior. Michael Dougherty, known to us from the scripts for X-Men 2 or Urban Legends-3 (who prefers what), this time acted as a director, reviving an ancient legend for lovers of mysticism and scary tales.
In the same city, in the same house, a large and not quite friendly family gathers. Unbearable relatives, offensive jokes, and in the center is a little boy Max, who still believes in Santa Claus and that Christmas should be filled only with happiness, laughter and fun. Disappointed in this big family holiday, the boy makes a very careless (in "Home Alone" style) wish ...
And although the acting is irrelevant here, I personally believe that Christa Stadler made literally the entire film, personifying the kind grandmother who bakes gingerbread men and tells ominous stories near the fireplace.
To summarize, Krampus is the kind of movie where the trailer flawlessly connects expectations with reality.