8It Follows (2014)
No, not a sequel to It, but it does likewise involve a shapeshifting monster methodically stalking a group of young people. In the world of It Follows, there’s a decidedly worse strain of STD than the usual bunch—one that summons a slow, methodical monster that shadows its victim unless they pass it on through sex, like a game of sexual Hot Potato. Once it kills its most recent victim, it starts back up the chain.
Part of the reason this monster landed on the list is the sheer paranoid fear it inspires in the viewer. If you didn’t walk home from the theater looking behind you for anyone slowly, silently following you, then you’re braver than we are. Plus, when it kills its victims, it’s in some sort of horrible, back-breaking sex, sometimes even while wearing the face of its victim’s parent. That’s a bad way to go.