The Internet in the place I'm staying stopped working Wednesday, and hasn't been restored. No one seems to know why it's stopped working, or when it'll return (or if they know, they aren't saying). This may cause problems for posting, since I'll either have to sneak it in at work, or drive 20+ miles to some place with wi-fi.
I did say I had a post I wanted to do on Wednesday, and two days late is better than never.
I said I expect some major brawl between the X-Men and the Inhumans, but at this stage, there isn't too much reason to fight (although apparently that didn't stop Cyclops?). The damage is done, punching the Royal Family of Attilan in the face won't fix things now. Granted, that's never stopped Marvel's heroes from punching each other, but let's assume for a moment it might.
There are still a lot of people who were fairly recently turned into mutants as a result of Cyclops' Phoenix-controlled-by-Hope Summers plan. There were also a lot of people recently having Inhuman genetics unlocked by Black Bolt releasing Terrigen Mist across the world. None of these people were consulted about these changes beforehand. Some jerkoff decided, "this is a thing that's happening to you now," and that's it.
Some people have adjusted. A lot of kids joined Logan's Jean Grey School, and Kamala Khan's obviously taken to her emerging super-powers. And you have people like Kamran, or those Hellfire Club kids that have seen this as an opportunity to further their own gains, and are seizing it. But there have to be a lot of people who haven't adjusted. None of the X-teams came to recruit them, or they don't know about New Attilan, or their powers are actively harmful to them. Lots of people have to have had their lives ruined by these events, and if they're a mutant, now they get the double-whammy that the Mists inadvertently sterilized them. Whoops.
It wouldn't be stretch for there to be a lot of angry mutants and Inhumans out there. First. angry at the people who did this to them without consent, and resentful of the groups trying to control them (Join my school! No, join my revolution! Move to our floating city in the Hudson River and join our rigid monarchical society!) Since a lot of the people affected on both sides seem to be younger folks, maybe they team-up against what they see as once again an older generation dumping its problems on their laps, then leaving them to deal with it. The reveal of the effect of the Mists on mutants might strain those groups.
So you have a lot of people with powers they didn't ask for running around, lashing out. You have the X-Men and the Inhumans each working to try and minimize the damage on their side of the street, and grudgingly working together when necessary (again, the fact Beast is working with the Inhumans reassures exactly no one on either side). The various Avengers teams are in the middle trying to keep everything cool, although they're being strained from within. Someone - probably Gorgon - gets a little too rough with a recent mutant, maybe because the kid seriously injured Triton or someone else, Colossus objects, and it turns into a whole big thing between the two sides now.
The various (still mostly non-super-powered) governments start to panic, which means we're moving perilously close to "unleash the giant killer robots!", and there are, of course, super-villains spurring the whole thing on. I knows he's essentially dead at the moment, but this seems like the sort of thing Apocalypse would be invested in. I can't tell if this new Squadron Supreme are good guys or bad guys, but they seem to be trying to operate secretly, so they'll accelerate their plans to take advantage of the discord.
Hopefully there wouldn't be too much heroes fighting each other. There could just enough of that to make cooperation difficult, to break lines of communication, which makes dealing with all the other problems harder. Plus, even within groups there could disagreement about what they should be focusing on. Sunspot's modified AIM team could try to work on searching for cures, while Steve Rogers' bunch could be trying to mediate between the sides, while the one with Sam Wilson and Kamala could be actively trying to respond to flare-ups of violence. Or the X-Men could disagree on how publicly they should get involved, while perhaps Medusa is in full damage control mode, but working to absolve her side and blame mutants (I don't have a real high opinion of the Royal Family's level of honor these days, but it wouldn't have to be that).
I don't have any solution for how you end it, though, short of reversing the stupid "sterilized mutants" thing. And even that doesn't address the issue of people who didn't want to be altered in the first place. Those folks might just have to remain as a group of factions that are active. Some more violent, some protesting, others trying to leverage their powers subtly, maybe manipulate politicians to produce results, or maybe trying to withdraw from society to form their own groups, if they feel the existing society has let them down badly enough.
I want to give a nod to Tom Foss, because I feel this post is at least partially inspired by his idea for a more sensible Civil War from a long time ago. He had a good idea about making more than a simple, two-sided conflict, introducing shades to the different sides, that seemed really applicable here.