SPOILER WARNING: The following article contains major spoilers for X-Men Blue #20, by Cullen Bunn, R.B. Silva, Adriano Di Benedetto, Rain Beredo and Joe Caramagna, on sale now.
When the time-displaced members of Marvel Comics' X-Men Blue first discovered versions of themselves still existed in the past (as if they never left), the mutants began brainstorming on its real meaning. Possibilities ranged from their presence in the current-day having created an alternate timeline, to them being chronal anomalies.
As it turns out, neither is the case. Another group of time travelers, the future Brotherhood -- Charles Xavier II, Raze, Beast, Zorn, Bruiser, Ice Thing and Old Man Deadpool -- traveled to the past and disguised themselves as the original X-Men, in a bid to rewrite history. Now, with this secret out in the open, the X-Men Blue team must stop their evil doppelgangers before the timestream collapses permanently, while also uncovering the truth behind their time paradox.
We're The X-Men Now
Charles Xavier is the man that founded the X-Men, with the dream that humans and mutants would one day live together in harmony. Of course, if you were to ask any random person, they'd say that's a very noble goal. Somehow, those qualities didn't get passed down to Charles' future son. When Charles II sees the original team of X-Men, he sees a group of mutants who ruined his father's legacy. Which is why he's tried on multiple occasions to change the past, only to be repelled. But once Charles II realized there was an empty void left in the past, he hopped at the chance, bringing his Brotherhood along for the ride.
Fortunately for our heroes, the Brotherhood only planned on facing Jean Grey, Cyclops, Beast, Iceman and Angel. The original X-Men have picked up a few more members since X-Men Blue launched, namely Jimmy Hudson from the Ultimate Universe, and Bloodstorm from the Mutant X alternate reality. Bloodstorm used her power to turn into mist to gain the upper hand on the Brotherhood, affording her enough time to free the X-Men.
Bring In The Reinforcements
Speaking of upper hands, the X-Men's travels through the timestream introduced them to other teams from different time periods, including the X-Men of 2099 and Generation X's Massachusetts Academy of the past. With their worlds collapsing from the time paradox, they also had a bone to pick with the Brotherhood. Which is why Beast used his borrowed future tech to teleport them to the fight.
Outnumbered, the Brotherhood quickly fell to the assembled X-Men superteam. Though the Brotherhood was defeated, they managed to escape back into the timestream. To quote Charles II, "There's always next time." With the Brotherhood gone, Generation X and X-Men 2099 head back to their rightful homes as well. The only thing left is a reunion with Professor X, and some long-awaited answers.
Time Paradox, Explained
During the earlier battle, Jean was able to find and free Professor X. He quickly reassures his students that this is, indeed, their world and their time. The reason Magneto created his time platform had to do with the fact that Charles seeded a telepathic summons for help through time. Once the Brotherhood struck, he let his thoughts pass from person to person, until the message finally got to the present day.
But now that the X-Men are back home, it would be so easy for them to stay and make sure nothing like this happens again. The only problem is, they've changed so much from when they originally left. One glaring example is Angel now has wings that can turn to fire! No, for the X-Men to return for good, it must be the exact moment from when they left.
Once the X-Men arrive back in the current-day, they tell Magneto everything, even though he was better off not knowing. Magneto's Brotherhood of Evil Mutants are still alive, though there are some other lasting ramifications to our world. For example, Beast still has his future tech, and the team has memories of their travels through time.
Of course, when it comes to time travel, it's best to not ask too many questions. The world's not totally upside down, so at some point, the original, younger X-Men do go home. Exactly when that happens, however, will remain a mystery for another time, and most likely, another massive story arc.