WARNING: The following contains spoilers for Way of X #4 by Si Spurrier, Bob Quinn, Java Tartaglia & VC's Clayton Cowles, on sale now

The mutants associated with the X-Men have increasingly grown willing to cross moral and ethical lines recently, all in the pursuit of making Krakoa into the paradise it was promised to be. But three mutants just crossed a major line, and in the process wiped out a host of mutant allies. W

hile trying to keep their investigation into Onslaught's return a secret, the cat may be out of the bag now that Legion and the Xorn Brothers were forced to effectively kill many of their mutant allies to stop Onslaught's corruption from driving them all to murder each other -- setting off a sudden and brutal mutant massacre.

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Onslaught Possesses Xavier

Since uniting with Nightcrawler, Legion has been crucial to the investigation of the return of Onslaught -- the malevolent psychic presence created by Charles Xavier and Magneto that went on to endanger the entire Marvel Universe. Now traveling through Krakoa as a psychic monster, Legion has been trying to root out the threat while not alerting it to his presence, as he fears Onslaught will lash out if it's properly warned. However, Legion's father -- Xavier -- is still wary of his son due to the threat he potentially poses to Krakoa. As Legion explains to him at the Green Lagoon, this is the entire reason Legion recruited the Xorn Brothers to be by his side -- so they can monitor him and destroy him if he becomes a threat to others again.

Despite his pleas to learn more about the investigation (and even giving his son the Krakoa Seed he requested), Legion refuses to tell Xavier more about the threat at hand. This results in an impatient Xavier reaching into his mind -- and seemingly bringing about a massive psychic assault on the other denizens of the bar. The other denizens of the bar are caught up in the psychic attack, quickly lashing out at each other and setting off a massive chaotic scene. But before the violence can spread, Legion commands the Xorn Brothers to help him -- with the trio unleashing a torrent of power strong enough to kill every other mutant present in the Green Lagoon. Thanks to the resurrection capabilities of the Five, the assorted mutants -- including Xavier himself -- should be revived with little harm done in the long run.

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But it's still a horrifying moment for everyone involved and a reminder of the stakes at play in Way of X. In essence, Onslaught set off a fresh Mutant Massacre, his actions leading to the chaos that requires a cleansing of the area. There are also a sobering amount of major casualties among the group, including Blink, Tempo, Blob, Doctor Nemesis, Dazzler, Pixie, and Loa. It also means that Onslaught is likely now aware of the true threat Legion's investigation really is, and will probably advance its plans to corrupt mutant-kind to counter him. Nightcrawler has also been trying to find a way to investigate Onslaught's influence, likely forcing the long-time X-Man to increase the hectic nature of his evolving philosophy.

Perhaps most notably, this massacre will likely make it impossible for Legion and Nightcrawler to continue to hide the threat of Onslaught from the rest of Krakoa. This may inspire more panic in a populace fully aware of what Onslaught can do when unleashed -- and potentially further play into Onslaught's hands. Hopefully, Legion's plans with the Krakoa Seed -- which seemingly involves creating a temple for the mutant race on Arakko -- can create something to unify the disparate corners of Krakoa against the malicious psychic presence, before it finds a way to truly do some lasting damage onto the island the evolving mutant culture.

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