Warning: This article contains spoilers for Powers of X #2, by Jonathan Hickman, R.B. Silva, Adriano di Benedetto, Marte Gracia, VC's Clayton Cowles and Tom Muller, on sale now.
Before House of X and Powers of X turned dramatically redefined the X-Men's status quo, Marvels' heroic mutants famously protected a world that hates and fears them. More than anything else in the X-Men's world, the Sentinels are the walking embodiment of that hate and fear.
As decades of stories like "Days of Future Past" have teased, the Sentinels will probably be the force that ultimately topples the X-Men and drives mutantkind to the brink of extinction.
Over the past few weeks, House of X and Powers of X have revealed that a Sentinel-controlled future the most likely dark future of Marvel's mutants. About 90 years in the future, the Man-Machine Supremacy has driven most mutants into deep space as a small team of X-Men defends what's left of Xavier's dream.
That future is seemingly ruled by Nimrod, an impossibly advanced Sentinel who has also time-traveled to the present day to cause plenty of trouble for the X-Men. While Nimrod is usually linked to one of the X-Men's alternate-future timelines, Professor X and Magneto realize that the creation of the Marvel Universe's main Nimrod is imminent in Powers of X #2.
As House of X #1 revealed, human scientists and spies from across the Marvel Universe have joined forces to form Orchis, the ultimate mutant-fighting organization. Along with the former X-Man Omega Sentinel, they've established a giant base inside a giant Sentinel head orbiting the sun.
While that initially appeared to be a Master Mold, a Sentinel that creates other Sentinels, this issue confirms it’s a Mother Mold, which creates Master Molds. Although Mother Mold hasn't been turned on, Xavier and Magneto believe this is the point in history when Nimrod is activated, likely drawing on memories from Moira X's past lives.
Although Nimrod usually hails from the "Days of Future Past" alternate-future timeline, he represents a tangible, existential threat that every member of the X-Men understands.
Shortly after Nimrod's debut in Uncanny X-Men #191, by Chris Claremont and John Romita Jr., it took the combined efforts of the X-Men and the Hellfire Club to defeat the super Sentinel. Thanks to a near-limitless array of powers based around his instantaneous adaptation abilities, he killed two members of the Hellfire Club's Inner Circle, went blow-for-blow with the Juggernaut, and severely wounded Nightcrawler and Rogue.
The X-Men have dealt with Nimrod and other threats like Bastion, who Nimrod's technology was used to create, but the potential creation of Nimrod in the main Marvel Universe represents an important marker in X-Men history that takes the team ever closer to the post-apocalyptic world of "Days of Future Past."
While Cyclops seems determined to destroy Mother Mold before it can create Nimrod, that mission could be doomed to fail before it ever begins.
In addition to ruling over Man-Machine Supremacy as a talkative tyrant with monstrous plans in a century, Powers of X has also shown Nimrod surviving almost 1,000 years into the future, albeit in a very different form.
While that could make the X-Men's struggle seem hopeless, its not entirely clear where Nimrod's allegiances lie in that distant future. During one of the X-Men's encounters with Nimrod in the '80s, the machine evolved to no longer see mutants as a threat and even helped the X-Men on one occasion.
Although that suggests that Nimrod could eventually outgrow his programming in some capacity, the Sentinel remains an imminent, existential threat to the X-Men and mutantkind as a whole, even if they're armed with Moira's knowledge of past futures.