When considering every villain who took on the Avengers in the MCU, fans will likely point to Thanos as the ultimate ‘big bad’. Thanos did actually defeat the Avengers, after all, and his accomplishments were only undone after the Avengers literally bent time and space to do so. However, in the grim future Marvel Comics has written for Earth’s Mightiest Heroes, the villain who beats the Avengers is revealed – and it’s not Thanos.
The futuristic landscape in which the Avengers have grown old, festering in their greatest failure, is chronicled in Avengers: Twilight. The book follows Steve Rogers after the Super-Soldier serum was removed from his body, and he officially retired from being Captain America. Steve stays in touch with Luke Cage and Matt Murdock, all of them old men disillusioned with the state of the world since the superheroes were forced to hang up their proverbial (and, in some instances, literal) capes.
Throughout Avengers: Twilight, the book refers to an instance many years ago where a number of people in New York were killed, and the heroes were to blame. Even some of Captain America’s fellow heroes, including Spider-Man, died on what came to be known as H-Day. On H-Day, or ‘Hero Day’, the Avengers failed to defeat one villain, and their failure led to the world hating them and forcing them to retire. And the villain they failed to defeat was Ultron.
In Avengers: Twilight #1 by Chip Zdarsky and Daniel Acuña, Rogers is invited onto a talk show to discuss a docu-series that sought to frame Red Skull as a secret hero, and Captain America as the man who got in the way of Red Skull’s ‘righteous’ efforts to take down Hitler from within. Obviously, Steve wanted to set the record straight, but once the cameras were rolling and they were live, Steve was bombarded with H-Day questions. At that point, readers got a pretty good understanding of what happened, including the fact that Ultron was responsible.
Without knowing the full details, it makes sense that Ultron is the one who took down the Avengers for good. Ultron had a personal relationship with Hank Pym, and he hated the Avengers with every fiber of his being. Ultron wasn’t trying to decimate the universe or court Death, his only goal was to see the Avengers squirm, and he used his unparalleled, cybernetically enhanced intelligence to do it. Ultron didn’t just beat the Avengers, he made the world hate them as much as he did, which is how they stayed beaten.
Ultron’s tenure in the MCU was shamefully short-lived, as he was defeated mere days after he came online in Avengers: Age of Ultron. Sure, he proved how truly deadly he could be in the What If? series, but that’s an alt-universe Ultron. Ultron in the MCU’s main timeline was nothing compared to MCU’s Thanos, but time and again in the comics, Ultron proves to be the worst of the worst, and Avengers: Twilight is just the latest example. Ultron’s hatred of the Avengers is unparalleled, as is his genius, and he needs to make a comeback in the MCU.
Ultron being the Avengers’ ultimate endgame in the MCU would not only redeem the character himself, but also more accurately portray Ultron’s arch-enemy status opposite the Avengers. Thanos never really cared about Earth’s Mightiest Heroes, they just kind of got in his way a few times. But Ultron hates the Avengers, and fans can feel that in the sad future shown in Avengers: Twilight, which is why it’s perfect that Ultron is the villain who actually beats them, not Thanos (and why Ultron should do so again in the MCU).