SPOILER WARNING: This article contains spoilers for Uncanny X-Men #4, by Matthew Rosenberg, Kelly Thompson, Ed Brisson, Pere Perez, Rachelle Rosenberg and Joe Caramagna, on sale now.
After decades of speculation and vigorous fan debates, Marvel has finally answered one of the most pressing questions in the Marvel Universe: Who is the most powerful X-Man?
Despite the publisher's irregular use of nebulous terms like "Omega Level mutant," debates in comic shops and on message boards usually end up discussing the same small handful of powerhouse characters like the telepathic Jean Grey and Legion, Professor X's reality-warping son. Now, Uncanny X-Men #4 establishes that X-Man, aka Nate Grey, is Marvel's most powerful mutant. In addition to his remarkable actions within the story, Jean Grey and Legion essentially confirm that this alternate reality version of Cable is the strongest X-Man, describing him as an above-Omega Level mutant.
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Over their past few adventures, the X-Men have been dealing with several crises, ranging from mutant riots to dinosaur outbreaks. At the end of Uncanny #3, a few bizarrely-dressed and seemingly brainwashed X-Men and villains arrived on the X-Mansion's doorstep and introduced themselves as the Horsemen of Salvation.
After Magneto and the other Horsemen promptly blew up Xavier's School in the last issue, this issue opens with the team returning to their apparent master, Nate Grey. In a dramatic attempt to save the world from itself and reshape it in his image, Nate telepathically reaches out to every mind on or around Earth and shares his vision for the future.
Moments later, Jean Grey appears to be shocked by that feat, stating not even Professor Xavier could do that, even "at his most powerful." And even though Jean's naturally an Omega Level telepath of the highest order and used to wield the universe-shaping power of the Phoenix Force, she still says that Nate's level of power was "unheard of."
Without breaking a sweat, his telepathic message connects with billions of minds simultaneously. He's strong enough to even reach Captain Marvel, who's in low orbit around the planet at that moment. On top of that, he already turned Magneto, Angel, Omega Red and Blob into his pawns, and put Kitty Pryde, the X-Men's current leader, and Apocalypse, one of the most powerful mutants of all time, in chains.
Later on in the issue, the reality-warping Legion underlines just how powerful Nate is by describing him as "more than" Omega Level, which is generally the term to describe Marvel's most powerful mutants. Legion, who's also an Omega Level mutant, claims that he feels somewhat responsible for X-Man's actions since he's essentially his creator. While Legion isn't always the most stable voice, he's not totally wrong about this.
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In the 1990s, Legion traveled back in time to kill a pre-supervillain Magneto in a misguided attempt to please his father, Professor X. When Legion accidentally killed Xavier instead, he inadvertently created a dark new timeline called the Age of Apocalypse, where the X-villain Apocalypse ruled a dystopian world.
The fan-favorite "Age of Apocalypse" storyline took over the X-Men's world for several months in 1995 and 1996, where it offered bold new takes on familiar heroes and villains. While Cable is a grizzled time-traveling soldier in the Marvel Universe, he was the young Nate Grey in the Age of Apocalypse timeline.
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Where Cable is the son of Cyclops and Jean Grey's clone, X-Man was genetically-engineered by the mad scientist Mr. Sinister, who used the genes of his world's Cyclops and Jean Grey. The ultra-powerful Nate Grey was one of the Age of Apocalypse's breakout characters, and his adventures continued on in the Marvel Universe after his home timeline was seemingly erased.
Throughout his 75-issue solo series, X-Man struggled to adjust to the Marvel Universe and deal with immense psionic powers that were slowly killing him. After befriending Cable, Cyclops and Jean Grey, joining them on a short-lived X-Men team, he evolved into a kind of mutant shaman. To defeat an alien that was trying to harvest Earth's energy on a cellular level, Nate essentially turned into a pure energy being and put a little of his power into every living cell on Earth in 2001.
When he returned a decade later, Nate had an encounter with Norman Osborn's Dark X-Men that left him in a drastically weakened state. After joining the adult New Mutants for a few adventures, he faded into the background of the Marvel Universe.
While he's been gone for the past several years, Nate will be a big part of the X-Men's immediate future. While X-Man appears to be central to the next several issues of Uncanny X-Men, he'll also apparently take center stage in the upcoming "Age of X-Man" crossover, which is due out in 2019.
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This issue certainly positions X-Man as Marvel's strongest mutant, but there's still a little bit of room for debate. The Phoenix Force doesn't factor into this issue, and that can boost Jean Grey or someone else's powers to universe-shaking levels. Another one of Legion's multiple personas might have a different assessment of his own abilities. And Franklin Richards, the ultra-powerful adolescent mutant son of the Fantastic Four's Reed Richards and Sue Storm, isn't as strong as he will be once he grows up.
While those technicalities will let the debates rage on, Nate Grey can still make a very strong claim to being Marvel's strongest mutant, for the moment at least. Before "Age of X-Man" kicks off next year, X-Man will continue to wield his powers in Uncanny X-Men, which is currently being released weekly.