Director Josh Boone has confirmed that the X-Men spin-off, The New Mutants, will be a horror movie. He told Entertainment Weekly:
"We are making a full-fledged horror movie set within the X-Men universe. There are no costumes. There are no supervillains. We're trying to do something very, very different."
Marvel had pretty great success branching out from the standard superhero models with Deadpool and Logan, so they'll probably find a way to make this work as well. A source close to the project has hinted that they'll be focusing on the mutants' teenage years, so there's also a possibility that their idea of horror is simply having to be around a group of teenagers. *shudder*