Children of the Atom: So we all agree that they're human, right?
I don't think so.
There was a whole lot of "nothing" here for a red issue. I'm inclined to think that there isn't "nothing" happening but some significant things that might not be obvious.
regarding the gate- it's not exactly clear to me what happened, but it looked like either they or the gate "freaked out" when they touched it. Humans just pass right through the gates without incident, so I don't think these kids are human.
We see also that Cerebro can't detect these kids at all...which is very strange. Speculation is that one of them is a TP and might be shielding them from cerebro, but "marvel guy" doesn't appear to be anywhere near powerful enough to do that, let alone experienced enough to shield himself that way from tech he knows nothing about.
And finally- these mutant kids all seem to have powers of mutants that are already established. Not a single one seems to be an original concept...and one of them seems to have more than one ability, which isn't typical.
"Cherub" has wings that look a LOT like Warren Worthington when he was in his "death" phase when they're active, but appears to have sonic powers like Banshee on top of that.
"Gimmick" is charging and exploding things like Gambit does.
"Marvel Guy" is a telepath obviously meant to be a callback to Jean.
"Cyclops Lass" has cyclops' optic blasts, but controllable and at a lower power level.
"Daycrawler" can teleport like nightcrawler does, and has his toes and tail....sometimes?
I...can't think of the last time I saw a team of people pop up that were ALL obvious rip offs of established heroes without a single original concept between them. Mutation especially should be random. These also don't appear to be super-wealthy or super-genius kids that could replicate those powers via technology either. At best Gimmick is good at sewing together costumes.
Best explanation that comes to me here that satisfies the above is that these aren't natural born mutants. Sinister made these. There was an earlier issue where he was complaining about being "banned" from making clones by Xavier, but intended to use a loophole to make "something new" that didn't fit that criteria.
Sinister has everybody's genetic material, so making new mutants with powers similar (but not exactly the same) as the original would fit that criteria. We know that in Life 9 he ends up making several different generations of Chimeras doing exactly this- these kids could be "proto-chimeras" or generation 1 chimeras that would be the first step in that. IF Sinister was making new mutants that way to get around his cloning loophole, he wouldn't be doing it on Krakoa, that's the easiest way to get caught. He'd establish a lab "somewhere else" and monitor them remotely.
This would explain why they don't show up via cerebro- Sinister is a powerful TP in his own right and well aware of what Cerebro is and wouldn't want Charles and company coming across his experiments before he was done with them. Designing these kids so that Cerebro doesn't detect them wouldn't be that hard.
These kids being "artificial" mutants might be what is causing the gates to freak out. The gates may be reading them as "something odd" that's neither mutant nor human and causing a reaction. Sinister might also not want them running through gates either for the same reason he wouldn't want them to be detectable via cerebro.