Ok, this is not a straight-forward big monster movie. And it's mostly a horror movie that subverts and embraces the genre. But it's worth checking out for the final act, where bloodbath barely covers the struggle that pits humans against supernatural monster things.
At first, "The Cabin in the Woods" plays out like a fairly straightforward parody of the Evil Dead movies. But by the time the climax rolls around, the plot veers in unexpected directions and our heroes are confronted with versions of almost every major Hollywood monster and killer in existence. In short, there's a lot of bang for your monster buck here.