Side note: I think that this means that Wolverine's body doesn't have Adamantium since it was grown the way that it was.
It's an interesting question. Archangel still has his metal wings, but they're organic metal.
Perhaps Proteus gave reality an additional subtle nudge as he made those eggs viable.

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I realize we have a new issue coming out today, but the past week has been busy for me, so I've only now been able to finish getting out my thoughts on last Wednesday's issue. So I'm going to go ahead with posting on that, then probably have more thoughts later once I've read "Powers of X" #5.
As uninteresting as the issue prior was, "House of X" #5 was every bit the opposite. Probably my favorite issue of the storyline so far.
Getting an explanation at last for all the resurrections is most welcome, as is the in-universe means by which it is being accomplished. Mutantkind is bringing itself back from the brink of extinction by creatively combining its powers in ways that would make Chris Claremont envious.
Even long-dead mutants like Synch of Generation X (killed off back in the year 2000!) can be retrieved to live again -- picking up right where they left off -- through an organically conceived procedure. Given that it utilizes Hope Summers as its lynchpin, this is also a natural development for her as one who was once lauded as the Mutant Messiah.
Just as importantly, this "Battlestar Galactica"-style Cylon-esque concept makes for a refreshingly fresh start for the X-Men and mutants at large. It's well past time that the constant shadow of genocide and the diminishing returns of non-shock-intended-as-shock-value deaths be given a rest.
Which is not to say it's all sugar and rainbows here as we head into the last quarter leg of Hickman's 12-part redirection of the X-Men brand. Fandom online seems to be sharply split over the resurrection mechanism, due in large part to personal ideological barriers or cognitive dissonance where the legitimacy of the restored characters' identities is concerned.
For some it is difficult to recognize these characters as the originals due to the genetic cloning process at work, despite the lengths to which the writer goes to emphasize that the deceased's souls are imbued into these husks via the collection and transfer of their memories.
Though this does unavoidably raise the post- and transhumanist high-concept philosophical quandry of "What is actually 'human'?" -- as seen often enough in sci-fi over the decades -- it isn't particularly uncharted territory for Marvel's comics in general nor the X-Men in particular.
The soul of Xavier himself recently came to occupy a body not originally his own (it belonged to Fantomex), and for that matter, Xavier's first original body was subsumed by a Brood queen back in 1983's "Uncanny X-Men" #167. His mind, however -- that is to say, his soul -- was transferred to a new husk cloned from tissue samples containing his DNA.
Similarly, the New Mutants Magik, Mirage, Karma, Magma, Wolfsbane, Cypher, Warlock, and Cannonball were all physically discorporated and then metaphysically erased by The Beyonder in 1986's "New Mutants" #37 before he collected "the wisps of energy and shadows of thoughts that [were] the sole remains" of them in "Secret Wars II" #9, from which he rapidly reconstructed their bodies and minds inside a giant incubator.
Perhaps even more poignantly, Wolverine's healing factor has been doing precisely this sort of thing for him for years, frequently reconstructing at one point or another every organic part of his body, except perhaps the proteins in his adamantium-laced skeleton. There has even been occasion that all the organic parts of his body have been burned off the skeleton and needed restoration at the same time (e.g. 2007's "Wolverine" #48). More than once his brain too has needed to be restored, with his consciousness -- that is once more to say: his soul -- coming back to awareness after a period in which he was described as temporarily being dead (e.g. the previously mentioned issue, as well as issue #65 of the same volume).
Coming to the ultimate example with Wolverine, we have even on one occasion (1987's "Uncanny X-Men Annual" #11) seen his healing factor -- albeit aided with a power-up from a cosmic artifact -- make fresh recomposition of his entire body, skeleton and all, from whatever cells were within a single drop of blood! While his original body lay dead on the floor, Wolverine's consciousness and memories were also in the new body.
Fandom has consistently accepted this sort of equivocation between characters' memories and their genuine essence before. Why not now?
Though there is certainly no reason to take issue with the mechanism of resurrection, that's not to say all is quite sugar and rainbows here with me either. As Luckystar. on CBR's forum put it, "I'm torn between 'this is genius' and 'this is a creepy cult, not relatable at all, and Storm sounds like a lunatic.'" It's awesome to see things going so well for mutants for once, but damn, this shit is still super creepy.
Granted, there's no way all this isn't supposed to be super creepy. Hickman is either heavily telegraphing something being amiss or setting up a twistless twist -- which would be a twist indeed.
Particularly with this issue establishing that the resurrection process may develop the revived X-Men to their "optimal and perfected form," one still has to wonder whether there has been some manipulation of them at work. "Optimal" according to whom?
Something still seems off about some of these X-Men for me.
Jean Grey does seem more herself in what lines she had this issue: she literally quotes herself about being "the only me there ever was" from a reply she gave Storm back in the "Inferno" crossover of 1989. Her timid behavior in "House of X" #4, however, and regression to the Marvel Girl codename and uniform still don't seem like a natural progression for her.
It is arguably almost as odd that, in the same issue as Jean's out-of-character behavior, Wolverine should ask Nightcrawler "what someone like me should expect" for an afterlife. Logan has literally been to Hell, as depicted in issues #1 through 5 of the volume of his solo series from 2010. He even escaped with the expectation that he would be going back one day.
Perhaps more pertinent to the overall plot of "House of X"/"Powers of X", though, where is Moira? For being the focal point of this storyline, we haven't seen her (as far as we know) for five issues now, and we've not seen her in the present day portions of the story at all. One begins to wonder if we've been misdirected in some way with regard to her as well.
Finally, why are people like Callisto, Marrow, Frenzy, Random, and even Daken arriving as part of the villain population?
Callisto has been an ally of and friend to the X-Men for three decades of publication history at this point. She was even an outright member of one incarnation of the X-Men-adjacent team Excalibur (alongside Xavier and Magneto).
Marrow and Frenzy have meanwhile both been memebers of the X-Men and affiliated teams in recent years. Furthermore, during 2017's "Secret Empire" crossover event, both mutants were also citizens of New Tian, the previous sovereign land belonging to mutants. Random was there as well.
Neither Marrow's membership in Magneto's short-lived new Brotherhood from last year nor Emma Frost's new Hellfire Club this year should be a problem either, as Elixir was with her on both teams yet has already been living on Krakoa for some time. Indeed, he is even one of the new mutant society's five most treasured denizens.
Obviously Magneto and Emma themselves have also been residing on Krakoa, and both have significant positions within the nation. Even Mystique -- another member of Emma's iteration of the Hellfire Club -- has been living on Krakoa, and she's arguably a far more questionable choice than just about any of those characters whose inclusion in the villain ranks I questioned above (Daken being the only possible exception).
Speaking of questionable inclusions, Sabretooth has already been granted amnesty on Krakoa, and he's definitely a more questionable choice than Daken or Mystique. Particularly Daken, in light of his reduced tendency towards sociopathy and progression more towards heroism for several years, as well as his own X-Men membership in "X-Men Blue." Even Mystique, with her repaired psyche (courtesy of Psylocke in 2016's "Uncanny X-Men" #14) doesn't elicit quite as much concern, and she is definitely still one to worry about more than Marrow, Random, Frenzy, or Callisto.
For that matter, anyone who isn't Sabretooth is infinitely less of a concern than the likes of Apocalypse, Selene, Emplate, Gorgon, Wildside, Mesmero, or Mr. Sinister -- all of whom were also welcomed home to Krakoa.
Most of these seven have literally no redeeming or humanizing qualities, and those who do have them to some extent are either an unrepentant mind-controlling mass murderer and serial rapist with a God complex (Mesmero); or a genocidal powermongering eugenicist with a God complex (Apocalypse). The others are simply altogether evil.
To summarize: Marrow, Callisto, Daken, Frenzy, and Random don't at all belong in the same ostensibly now-repentant grouping as Selene, a sadistic energy vampire who aspires to subjugate all life; or Gorgon, a cruel butcher who aspires to
end all life; and don't even get me started on Mr. Sinister, who isn't a natural mutant in the first place, and who is obviously going to try screwing everyone over just so he can get more mutant (especially Summers and Grey) tissue samples to study.
Still, it's nice to see these characters again, as well as Hope, Eva Bell, and Goldballs -- and it's also nice to see that Marrow's back in the costume she wore when she was with the X-Men about 20 years ago.
I know it seems like I've been mostly griping here, but I really did enjoy this issue and am quite excited to read "Powers of X"#5 later.
Other thoughts:
- Is Proteus actually Xavier's son? One of the data pages tells us "There has been no experimentation regarding what happens when you combine a mutant MIND with a HUSK not their own," but the same data page tells us that "Proteus' backup mutant husk is always created from the genetic base of Charles Xavier."
- Did Moira birth Proteus for the sole purpose of him being able to serve a role in the mutant resurrection machine?
- Sinister's mutant DNA comes from John Proudstar (the original Thunderbird), who has been deceased for many years. What happens if they try to resurrect him? Would Krakoa be confused?