The New Mutants Trailer Breakdown: 8 Things You Need To See
2. Mirage Creating Some Terrifying Scenes
Theory time: most of the evil shenanigans going on in this film are due to Mirage.
For those not in the know, Mirage is a mutant who has the ability to create terrifying illusions to disorient and defeat her opponents. The trailer introduced the character with a narration from Reyes, talking about how baby rattlesnakes are more dangerous than their older counterparts, in that they haven't managed to control "how much venom they secrete."
While comparing a young Mutant to an animal is problematic for a whole host of reasons, the metaphor could fit with the story Boone et al. are aiming for. We see throughout the trailer that Mirage is surrounded by horror - she notices blood falling out of her fingertips, the walls literally come alive and torment her, and then there's the spooky looking demon thing too.
Could it be the case that, because her powers are manifesting for the first time (and she hasn't yet learned how to control them), that all of the film's horror elements are coming from her?
It's possible, and while that might sound like a cop-out in some respects, it would be a great explanation for why the film is boasting a newfound horror motif.