Consider, if you will, the scratchy yellow font on the poster for The New Mutants. Harsh against the blacks/grays of the background, it seems to be more of a warning than a reassurance.
The implication – borne out by a statement in the trailer that ‘baby rattlesnakes are more dangerous than adult rattlesnakes’ – seems to be that young mutants are the things that go bump in the night. They are the scary beasties.
The New Mutants premieres on April 13, 2018.