Marvel is a titan in the comic book industry, thanks to characters like Spider-Man, Iron Man, and the X-Men. Since the Silver Age, this lot has gone through significant changes, evolving with the times while dealing with countless threats and developments.

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The Marvel timeline has experienced multiple events throughout the years, shaking these characters' lives. From conflicts to literal wars, these incidents threatened to alter the very foundations upon which the Marvel Universe stands. And while Earth's heroes always managed to come out on top, many of these events had significant consequences still felt to this day.

Inferno

New York invaded by demons in X-Men comics

New York City has faced countless threats during Marvel's history, but few match the time when an army of demons from hell invaded it. Comic book fans are well aware of the Inferno event, which turned NYC into hell on Earth and impacted every hero living in the city.

Inferno was one of the most significant moments in X-Men history. It featured the corruption of Illyana Rasputin's soul, turning her into the Darkchilde, and the rise and fall of the Goblin Queen, AKA Madelyne Prior. In many ways, Inferno was the X-Men's first genuine crossover, featuring multiple titles and storylines happening simultaneously and leaving lasting repercussions, some of which are still being felt.

Age Of Ultron

Ultron with Hawkeye reflected on his helmet in Marvel comics

Unlike its big-screen adaptation, the Age of Ultron in the comics is an actual age. It involves everyone's least favorite AI, Ultron, conquering the Earth with an army of Sentinels. The storyline also features plenty of time-traveling shenanigans, including a trip to the past in which Wolverine kills Hank Pym, thus preventing him from creating Ultron in the first place. Of course, the plan backfires, and he returns to a present where Earth is under Morgan le Fay's control.

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Ultron himself plays a supporting role in the story, which soon turns into an examination of past, present, and the legacy of Marvel's heroes. The ending is also completely bonkers, featuring Galactus and even Angela. The event would also directly lead into Avengers AI, cementing its place as one of the most important in the new millennium.

Dark Reign

Iron Patriot and the Dark Avengers

The aftermath of Secret Invasion allowed for Norman Osborn to take center stage. Osborn, a long-time enemy of everyone's favorite friendly neighborhood Spidey, was one of Marvel's most respected villains, but Dark Reign elevated his status and cemented him as one of the most dangerous men in the Marvel Universe.

Assuming control of Earth, Osborn creates a SHIELD replacement and becomes a high-profile hero, an Iron-Man substitute known as the Iron Patriot. He then forms the Dark Avengers, creates HAMMER, and launches a campaign against the Secret Avengers. Dark Reign features multiple Osborn-centric storylines that perfectly portray his evil genius. Indeed, his actions caused numerous problems for Earth's mightiest heroes.

Avengers First Assemble

Loki faces the Avengers in Marvel Comics

In 1963, the Avengers first fought the evil Asgardian God of Mischief, Loki. Brought together by Rick Jones, Marvel's ultimate sidekick, the original line-up included Iron Man, Ant-Man, Thor, Hulk, and the Wasp. Together, they defeated Loki and decided to form a team that would forever alter Marvel's course.

It's hard to imagine how the Marvel Universe would look without Earth's mightiest heroes protecting it. And while it's true that the Avengers were, for a long time, second best to the X-Men, the MCU redefined their purpose and turned them into arguably the best superhero team of all time.

The Infinity War

Thanos with the Infinity Guantlet in Marvel Comics

Comic book fans know Thanos began as a villain for cosmic characters like Captain Marvel before ascending the ranks to become one of the most dangerous beings in the Marvel Universe. Infinity Gauntlet put him in the spotlight by having him reunite the six Infinity Gems, gaining omnipotence. He then erases half the life in the universe, prompting Adam Warlock to reunite the remaining heroes to stop the Mad Titan.

Infinity Gauntlet elevated the stakes higher than ever before and dared to feature a universe without half the population. However, it backtracked and reverted the universe to its initial state at the story's end. The event still left a significant mark in the Marvel Universe, mainly thanks to Adam Warlock keeping the Gauntlet and the Gems.

Secret Invasion

The Skrulls with lightning behind them in Marvel Comics

The Skrulls took center stage in 2008's Secret Invasion. The story followed the aliens as they began an invasion on Earth after secretly replacing several key figures in the Marvel Universe over a prolonged period.

Secret Invasion is one of the most ambitious events in comic book history. It destabilized the entire Marvel Universe, effectively rehabilitating many teams, including the Avengers, the Fantastic Four, and the Thunderbolts. The war confirmed the Skrulls as a threat of considerable danger and left the superhero world in shambles, leading up to Norman Osborn's Dark Reign. The upcoming series Secret Invasion will adapt this iconic storyline, and fans can't wait to see how the MCU will look after it ends.

Civil War

Spider-Man without his mask confessing his identity in Marvel Comics

The conflict of ideologies between Iron Man and Captain America was apparent since the Avengers' early storylines. However, tensions escalated when the US government passed the Superhero Registration Act, dividing the Marvel Universe into two sides, with Spider-Man caught in the middle.

Civil War is one of Marvel's most overtly political storylines. It featured some of the most iconic moments in modern superhero history, including Spider-Man revealing his civilian identity to the world. Civil War also ended with a significant shift in the Marvel balance of power, with Tony Stark becoming director of SHIELD and Captain America assassinated by a brainwashed Sharon Carter.

The Dark Phoenix Saga

Jean Grey as Dark Phoenix in the cover of X-Men

Jean Grey's descent into tyranny remains a landmark moment in comic book history. For years, Jean was the ultimate heroine, the poster child for what a female hero should be. The Phoenix Force's arrival changed that, turning her into a despot who annihilated entire stars to satiate her undying hunger.

The Dark Phoenix Saga still holds up to this day and remains a pivotal moment in comic book history. It altered the X-Men's entire purpose and introduced a massive threat that would keep haunting them well into the 21st century. It was also a watershed moment for female characters in comic books, placing a woman as the most powerful being in the Marvel Universe.

Secret Wars

Multiple Marvel heroes fighting in Marvel comics

Secrets Wars is one of the most daring events in Marvel history. It featured the destruction of multiple alternate universes, with the Earth in each one combining into the patchwork planet Battleworld. It also includes a version of Doctor Doom that goes by God Emperor Doom, which is just incredible.

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As a direct result of the event, the Ultimate Universe got destroyed, and several key elements, most notably Miles Morales, made their way to the mainstream Marvel Universe. The story also ended with the apparent death of the Fantastic Four and Namor. For all intents and purposes, Secret Wars was a soft reboot of the Marvel Universe, and what better way to do it than via a battle royale parallel universe?

House Of M

Scarlet Witch creates House of M reality in Marvel comics.

The Scarlet Witch has a wide range of powers that make her among the most dangerous beings in the Marvel Universe. When she reaches a boiling point, she creates a new world where everyone has what they desire, but soon discovers that perfection comes with a price.

House of M resulted in the disappearance of nearly every mutant in the Marvel Universe after Wanda utters the three most iconic lines in any X-Men comic book: "No more mutants." The event's repercussions lasted for years and launched a new age for the X-Men. The MCU included certain elements in WandaVision, but the real adaptation will come once Doctor Strange in the Multiverse of Madness finally premieres in 2022.

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