Bh! Rachel's a Grey/Summers -- her being brought back promptly doesn't count... Hey, they can always kidnap an unsuspecting Shard from an alternate timeline, right?
I just figured they were trying to work within some rules with process, some of the rules just to have limitations for storytelling and some rules to avoid having to think about how it really works. AU characters have always kind of had to be treated differently.
Being an AU character there are already plenty of ways to bring Shard to this timeline if they wanted, and not just make her another Krakoan era copy and paste. It would make her entrance stand out and generate interest in her character and the story around it.
Malcolm and Randall should come back too! At least they were physically in 616. It’d be nice to give them more than twelve seconds of screen time before killing them so Bishop could join the X-men.
That's not how it worked though. Wanda's spell allows them to get backups from all previous points in time and space but it didn't magically conjure DNA, hence why Sinister's database and Sinister himself are still relevant. Like at no point has anything ever been said or even hinted about them not using the same resurrection process or not needing DNA or having more access to DNA now than they did before the spell....the spell simply broadened the scope of how and where they get what they put into the bodies once grown. And they did have Proudstar's DNA, that was never an issue, before the spell they simply didn't have a back-up for him because he died before the Cerebro back-up system was designed. But Sinister's own mutant gene is literally modeled off John Proudstar's. Shard's resurrection is the opposite problem of what John's was - they have a back-up, just nothing to put it in without her DNA.
Of course, even that isn't really an issue.....she was a consciousness without a body in the modern 616 to begin with, so it begs the question why while figuring out a way to get a DNA sample for her, they couldn't just upload her backup into the hologram light projection 'body' Forge made for her in the first place. Or something similar. Hell, its not that different from what Moira and Arnab are doing over in X Deaths of Wolverine with the only difference being Shard's literally done this before.
Also, theoretically there's nothing stopping Elixir or various geneticists from making Shard a new body related to Bishop by using his DNA and tweaking it to be more like hers based on their own understanding of genetic modeling or whatever. I know various datapages have made a big deal about how they've no idea what would happen if they put a mutant's back-up in someone else's body instead of their original, but that's always been bullshit given we know for a fact that Proteus' husk is based off of Charles Xavier.
Ultimately, the only reason we don't have Shard back yet is because nobody seems to care enough to bring her back, which sucks. But logistics have never been the issue.
I see Shard as one of those characters with crossover potential. She could stay with the X-men, or hop over to one of the other groups, including the Thunderbolts, the Avengers, Alpha Flight, Guardians of the Galaxy, Marvels, SHIELD, etc. Maybe have her occasionally team up with Blade, Elektra, Captain America, Misty Knight, Luke Cage, Hawkeye, Black Panther, or the Ghost Rider. Even "Shard & The Winter Soldier" has a nice enough ring to it.
You're right. The "how" really is less important if there is a will to revive the character. It could be as simple as Shard self-resurrecting from her own light essence, or as complicated as the Krakoan protocols. Hopefully, someone makes it happen...even if it means altering her powerset so that she could never rez herself the same way again.
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