Collects Extraordinary X-Men (2015) #17-20, X-Men Prime (2017) #1. Extraordinary X-Men versus Uncanny Inhumans! The X-Men have learned that the Terrigen Mist — the source of the Inhumans’ powers, but lethal to mutants — has reached an irreversible saturation point. Earth is on the verge of being rendered uninhabitable to mutantkind. And now the X-Men see no other option than to strike against the Inhumans to ensure their own survival. But one X-Man doesn’t take the decision lightly. Storm has literally led her teammates through hell and back, but will she command them in battle against their longtime friends and allies? What will war mean for Forge, Old Man Logan, Magik and Jean Grey? And if the X-Men come out the other side, what will be the cost? One Extraordinary era ends as another begins!

The fate of mutantkind is decided here! Staring down the threat of extinction once more, veteran X-Man Storm pulls together the team she'll need to ensure her race's survival. Together, these EXTRAORDINARY X-MEN will struggle with the familiar burden of being hated and feared, while facing threats the likes of which they've never seen. Here's hoping they survive the experience! COLLECTING: EXTRAORDINARY X-MEN (2015) #1-5.

Mutantkind is an endangered species once more. But what better way to ensure your people see the future.than to skip ahead right to it? As the mutant race's last hope is jettisoned into the time stream, the Extraordinary X-Men make a startling discovery: the fate of their kind is about to fall into the hands of one of their most formidable adversaries... the immortal Apocalypse. Now, the X-Men race into a perilous future, desperate to reclaim what was taken from them... and completely unaware of the horrors that await them. Collecting Extraordinary X-Men #6-12 (STC).

The X-Men confront the Inhumans in the most uncanny conflict of all! Since the discovery that the Terrigen Mists - the key to unlocking an Inhuman's hidden potential and powers - are lethal to mutants, the X-Men and Inhumans have been locked in a cold war. But now things are heating up, and about to boil over! As the Terrigen seeps into the Earth and reaches an irreversible tipping point, the X-Men are spurred into action to ensure the future of their species! And for Jean Grey and Fantomex, this means taking out of commission the Inhumans' deadliest weapon: Karnak! The Marvel Universe will be rocked by IVX! COLLECTING: UNCANNY X-MEN 16-19, ANNUAL 1

Desperate times call for a darker team of X-Men! With mutantkind in extinction's crosshairs once more, Magneto leads a group of the deadliest that homo superior has to offer to fight for the fate of their species! Refusing to accept even one more mutant death, the most ruthless possessors of the X-gene on Earth -deadly warriors such as Sabretooth, Fantomex, Mystique and Psylocke -have banded together to proactively mow down their enemies. But with a team populated by killers, can they stay away from each other's throats long enough to take down their targets? And can the Master of Magnetism curb his own homicidal instincts long enough to find out who's trying to speed up mutantkind's descent into the grave? It's X-Men with the emphasis on Uncanny! Collects UNCANNY X-MEN #1-6.

Collects Uncanny X-Men (2016) #16-19, Annual #1. The X-Men confront the Inhumans in the most uncanny conflict of all! Since the discovery that the Terrigen Mist — the key to unlocking an Inhuman’s hidden potential and powers — is lethal to mutants, the X-Men and Inhumans have been locked in a cold war. But now things are heating up, and about to boil over, as the X-Men are forced into drastic steps to ensure the future of their species! But when Magneto goes too far, what will be the repercussions of his dramatic actions when the battle ends? When she left his team, Psylocke vowed that if Magneto stepped out of line, she would end him. Is she about to make good on that promise? Plus: A dead X-Man returns, and so does Domino!

Collects Extraordinary X-Men #13-16, Annual #1. An ancient evil stirs in the periphery of Limbo, consuming mystical realms — and little does Magik suspect that the X-Men’s newest charge is drawing this World-Eater straight to X-Haven! Meanwhile, Colossus rampages across Earth as a Horseman of Apocalypse! Can Nightcrawler and Iceman wrest their friend from his evil influence? As the World-Eater bears down on Limbo, everything Magik cares about is on the line: her ward, her brother and the world’s surviving mutants. What will it cost to save them all? Plus: When the Terrigen Cloud threatens a jail, and the warden refuses to protect its mutant inmates, the Extraordinary X-Men take matters into their own hands and stage a prison break! And when Moon Girl takes it upon herself to solve the Terrigen crisis, she may just find an unlikely ally!