Ultraviolence at the holidays takes on many forms. I’ve seen children tear open presents in ways that would garner a hard-R rating for graphic, disturbing intensity. At the movies, I’ve seen what some of you have seen — “Dead Snow,” for example. It’s technically an Easter movie, but all that snow makes it feel Christmassy. Norwegian director Tommy Wirkola’s 2009 festivus of gore imagines the story of medical students on a skiing holiday sharing the slopes with a horde of Nazi zombies. Lively, insanely gory stuff, it’s very much “in the wild-eyed spirit of Peter Jackson’s ‘Dead Alive’ and Sam...