Warning: This article contains major spoilers for House of X #4, by Jonathan Hickman, Pepe Larraz, Marte Gracia, VC's Clayton Cowles and Tom Muller, on sale now.

Marvel's House of X is built on death. More specifically, it's built around the numerous deaths of Moira MacTaggert, who's secretly been using her reincarnation powers to gather knowledge that can prevent the X-Men's most dire futures.

While Moira, Professor X and Magneto have used that knowledge to establish the mutant nation Krakoa, they've also pinpointed the creation of Nimrod, the ultimate Sentinel, as the turning point in mutant history. To stop the anti-mutant forces of Project: Orchis from developing Nimrod, Cyclops assembled a "suicide squad" of X-Men to keep the robot from coming online by any means necessary in House of X #3.

In House of X #4, the X-Men accomplish their goal, but that entire team, which includes several of Marvel's most prominent mutants, is seemingly killed in the attack.

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After an Orchis operative destroyed part of the group's space station to damage the X-Men's spaceship at the end of the previous issue, this issue reveals that Archangel and Husk, a former member of the young mutant team Generation X, were killed in that explosion.

As the X-Men soldier on with their mission, Mystique is sucked into the vacuum of space before she can complete her crucial role in their plan. Monet St. Croix, another Generation X graduate better known as M, seemingly perished after saving Jean Grey's life and shifting into her razor-sharp Penance form.

In one of the issue's most affecting moments, Nightcrawler and Wolverine give their lives to finish Mystqiue's task and send the Mother Mold Sentinel that's key to the development of Nimrod into the sun. Finally, Cyclops is killed by Orchis' Dr. Alia Gregor, and Jean Grey's escape pod is destroyed by a group of Sentinels. Before her demise, she telepathically informs Xavier of the team's success and the unbearably high cost of their victory.

Any one or two of these deaths would be a major event in the X-Men's world. Together, however, the loss of so many major heroes could feel like one of the darkest moments in X-Men history. Outside of Mystique, each of these characters makes a heroic last stand or else receives a moment that speaks to their essence and gives them a fitting send-off.

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Despite all that, some, if not all, of these deaths don't appear as permanent as they may seem at first glance.

Cyclops, Wolverine and Jean Grey appear alive and well on the cover of Hickman and Leinil Yu's upcoming X-Men #1. Although it's not yet clear how they might return, or if the other mutants who died in this issue could be resurrected too, their presence on the covers all but confirms their imminent resurrections.

While the X-Men still grieve their fallen friends in this issue, Xavier's narration makes the moment seem more defiant than mournful, especially when paired with the statistics about mutant death that are included throughout the rest of the issue. In the final pages, Xavier laments the unusually high number of mutant deaths before seemingly cursing the very idea of death with the phrase, "No more."

While death has always been something of a revolving door for the X-Men, Cyclops, Wolverine and Jean Grey all already made high-profiles returns within the past year and a half, which makes their apparent deaths here all the more suspect.

House of X #1 kicked off by quietly reviving deceased characters like Banshee and Sophie Cuckoo immediately after one of the deadliest periods in X-Men history, likely through whatever might bring this issue's fallen X-Men back to life. However, if Wolverine and Nightcrawler's brief pre-death conversation about the afterlife is any indication, the X-Men may not even realize that these resurrections are happening.

Between the pods that seemingly birthed mutants in House of X #1 and the impending arrival of resurrection-happy villains like Mister Sinister and Apocalypse, House of X would seem to have a number of potential ways to bring dead X-Men back to life, each with its own set of potentially massive implications.

With the central importance of Moira's reincarnations, House of X is built around the idea of rebirth as much as it's built around death. But even if the resurrection of the X-Men who died in this issue seems predictable, House of X has consistently confounded expectations in a way that almost guarantees that their likely return won't be as straightforward as it seems.

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