X-Men: 10 Characters That Must Appear In The New Mutants Movie
3. Emma Frost & The Hellions

Every protagonist super team should have an antagonist super team to fight. If not, then you have to have a Big Bad that’s powerful enough to take them all on. That bring up its own set of issues, not least of which is that a being that disgustingly powerful ends up skewing the whole plot of the film. You end up asking yourself suspension-of-disbelief-killing questions like, if Mister X is so all-fired fancy, why doesn’t he just do Plan Y instead?
Since no good storyteller should tell a story that accidentally poses questions it can’t answer, the solution is to match the protagonist evenly with the antagonist. In the case of the New Mutants, that means presenting them with a team of bad guys for them to defeat - and luckily for us, X-Men continuity has already given us the Hellions.
The White Queen of the Hellfire Club (who you may remember from such godawful performances as January Jones in X-Men: First Class) has her own little class of student mutants. Many of them were direct analogues for members of the New Mutants - for example, Jetstream was a human rocket just like Cannonball; Empath could sense and manipulate emotions, paralleling Karma’s power of possession; Catseye was a werecat to pair off with Wolfsbane (although purple, for some reason, and convinced that she was a cat that could transform into a human).
The rather lovely thing about the Hellions was that they weren’t just an evil superteam. As a rival class of teenage mutants, relations between the Hellions and the New Mutants was more akin to competing social groups, groups that would occasionally crossover and even bond with one another. Catseye’s first response upon meeting Wolfsbane isn’t to attack her, but to exclaim that as fellow shapeshifters, they should be best friends: it’s the delight of one teenage girl over meeting another with similar interest.
Sadly, Marvel didn’t treat the Hellions as well as it did their more heroic counterparts. They weren’t really bad kids, they just had a bad (ie, evil) teacher: but that didn’t stop them being cannon fodder in the Hellfire Club’s more adult battles, being massacred for the most part by sociopathic villain Trevor Fitzroy. The resultant guilt was instrumental in the White Queen’s reform over the years into an ally of the X-Men, and today she remains a key member, and even occasional leader. Just get someone else to play her, for the love of god.