WARNING: This article contains major spoilers for Jean Grey #11, by Dennis Hopeless, Victor Ibanez, Alberto Alburquerque, Jay David Ramos and Travis Lanham, on sale now.
Ever since the original, younger X-Men were brought from the past to the current-day, there has been a question of just how much their presence has affected the Marvel Universe's timeline. Compounding that mystery is the fact that each of the team members has changed drastically since arriving in the here and now. Cyclops learned he grows up to become a mutant pariah and was forced to watch his older self die from M-Pox disease; Beast, a brilliant scientist, began to dabble in magic; Angel, while on an adventure with the Guardians of the Galaxy, received a massive power boost from the Black Vortex; Iceman admitted to his friends that he's gay; and Jean Grey discovered she goes on to become possessed by the Phoenix Force, and then died herself.
Another big development in Jean Grey's world is the return of her long-dead adult counterpart in the Phoenix Resurrection. The five-part miniseries saw the Phoenix Force bring adult Jean back to life in order for the telepathic mutant to become its host once again. As powerful as the Phoenix is, the assumption was that the cosmic being simply used its abilities to resurrect adult Jean. However, Jean Grey #11 reveals there was more to the story -- much more.
In order to revive the adult Jean Grey, the younger Jean needed to be sacrificed.
Back To Life, Back To Reality
Jean Grey #11 follows the spirit of the deceased, younger Jean in the wake of her death at the... talon(?) of the Phoenix Force. After being forced to relive experiences from previous Phoenix hosts, Jean learns she was being held in the White Hot Room -- a nexus between all Phoenix hosts and their eternal flame. Once the Phoenix has bonded with a host, they leave a piece of themselves in the White Hot Room.
It's here that young Jean and the Phoenix finally get down to the business of working through their problems. Jean has spent the entirety of her solo series actively avoiding the Phoenix, and when it finally catches up with her, she ends up dead. There's a pretty important reason for this -- young Jean rejected the Phoenix, but it still needed a Jean Grey to merge with. Thus, the Phoenix got creative and killed young Jean, an event that somehow allowed the events in Phoenix Resurrection to unfold.
Of all its former hosts, the Phoenix has always had a soft spot for Jean Grey, referring to her as the perfect host and vessel. However, the time-displaced Jean is not the same person it bonded with previously, so the Phoenix called an audible. And that audible wouldn't be possible if X-Men Blue's original X-Men weren't stuck in the present.
Thankfully for both Jean Greys, the resolution of the original X-Men's time paradox left them in the current-day. If they ended up back in the past where they truly belong, the Phoenix wouldn't have been able to resurrect adult Jean. And now, young Jean is even back to life as well, which should make for some interesting times as they begin to occupy the same space in the Marvel Universe.