Considering this a new character will force me to go back for at least two other guys I neglected in the past, but since the Multiverse is becoming more and more pivotal in the MCU, both with the current WandaVision and in the future Doctor Strange and the Multiverse of Madness, it’s a safe bet that more alternate versions of known characters will pop up. So let’s start with last week’s episode All-New Halloween Spooktacular, as it turned out not only that Pietro knows quite a lot about what his sister Wanda has been doing in Westview, but also that he is still effectively dead, as in one scene we can see him as an animated corpse ridden with bullets, as we left him (well, not exactly the Evan Peters version from the X-Men movies, but rather the Aaron Taylor-Johnson version from the MCU) in Avengers: Age of Ultron. This creepy zombie version actually exists in the Marvel Universe, and is not pleasant at all. Let’s see together our first character from Earth-2149, aka Earth-Z.
Apparently, the life of Pietro Maximoff, aka Quicksilver, on Earth-2149, was very much the same of the Quicksilver of Earth-616, at least until a Sentry from another dimension, Earth-91126, arrived in that world, carrying a deadly disease that turned several superheroes into flesh-eating zombies. At the time, the infection was contained in New York City, and Quicksilver was called by Nick Fury to the S.H.I.E.L.D. Helicarrier, where he joined the resistance against the undead. Ironically, it was Quicksilver’s presence that made everything pass the point of no return, and that doomed the entire 
world. After assessing the situation as serious as possible, Fury organized the remaining heroes to try and kill as many zombies possible, on the ones side, and to research for a cure, on the other, in order to contain the epidemic in the most effective way: Quicksilver was sent on the surface, and here he did his best to stop the undead as he spotted them… but then he saw Zombie Black Cat approaching his sister, Scarlet Witch, helpless before her. Without losing a moment to think about it, Pietro saved his sister, and rushed her to safety… but unfortunately “Scarlet Witch” was actually Zombie Mystique, who bit him on the neck as he was still running. From there on, the epidemic became unstoppable: Zombie Quicksilver traveled across borders, across oceans, across mountains, biting and devouring at impossible speed, moving faster than Fury and his Resistance could think. If the initial efforts from heroes and authorities had contained the plague to New York, the presence of Zombie Quicksilver nullified their work, and the plague became a global threat: the ones who weren’t infected yet became food for the undead, hunted and devoured everywhere on the planet.
Soon, “fresh meat” started to be a rare item on Earth, and Zombie Quicksilver, along with the other undead, grew restless, instinctively moving towards the few remaining living beings, among which his own father, Magneto, who still protected a small pocket of humanity. Magneto was helped by the Fantastic Four from another reality, Earth-1610, and managed to send away some humans before the pursuing Marvel Zombies managed to devour them. After that, the Silver Surfer arrived on the planet, a most-welcome newcomer. Several undead tried to consume him, including Zombie 
Quicksilver, but only a bunch of them, Iron Man, Colonel America, Luke Cage, Spider-Man, Wolverine, Giant-Man and Hulk, managed to do it, gaining cosmic powers in the process… and testing them on their fellow undead, before leaving the planet to explore space first, and other realities next. Thanks to his speed, Quicksilver managed to avoid the blasts of cosmic energy, and kept wandering the planet, finding nourishment here and there, and rejoining his sister, now Zombie Scarlet Witch. The Maximoff twins eventually found a comfortable place at the employment of Zombie Kingpin, who had obtained the service of many superpowered undead in exchange of seemingly endless supplies of living meat. The Kingpin’s secret was his monopoly of cloning vats, that he used to “pay” his subordinates by multiplying indefinitely the few living humans remaining on the planet. Under his new master, Zombie Quicksilver fought, ran, ate, until a new enemy, not exactly living and thus impervious to the plague, appeared: Machine Man, coming from Earth-616, who managed to destroy Zombie Kingpin’s cloning vats. Machine Man tried to escape on a motorbike, but nobody could outrun Zombie Quicksilver, as he would have soon discovered…
Pietro Maximoff used to be many things: impulsive, heroic, arrogant, determined, stubborn, a restless fighter and a lovely brother, a brave defender of humanity and even an hereditary prince… but now there is only the hunger, and that he follows wherever it takes him. As Zombie Quicksilver, he possesses all the speed and related powers of his Earth-616 counterpart, but being an undead, he is also impervious to any wound, even lethal ones, as long as his brain is not destroyed, and he’s compelled to consume human flesh not to decay. A monster fast as lightning, Zombie Quicksilver is the main reason for which the plague spread beyond control on the planet, a harbinger of death who can reduce a grown man to a bloody skeleton in the blink of an eye.
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