The Avengers have been around for over 57 years now, and they have undergone several lineup changes, as well as hundreds upon hundreds of different members. In that time, they have also been involved in some of the greatest story lines in comic book history. These epic stories have led to Earth’s Mightiest Heroes dominating the big screen for the better part of the last decade. With that in mind, let’s take a look back at some of the top Avengers stories of all time, and examine what they meant to the continued success of the franchise.

#10 Cap’s Kooky Quartet

The Avengers went through their very first lineup change in Avengers #16. Stan Lee wanted to distance the comic from its DC counterpart, the Justice League. Therefore, Lee removed all the heavy hitters on the team, replacing them with a flawed group of ex-villains and keeping Captain America on as the leader of the team. Hawkeye, Quicksilver, and the Scarlet Witch put their villainous pasts behind them and joined Cap in what would eventually be known as “Cap’s Kooky Quartet.”

This foursome lasted for roughly 12 issues, and served as the first real test of whether or not the Avengers would stand the test of time. During this period, the Avengers came up against some major villains, including their first battle against Kang the Conqueror. Hawkeye would go on to be one of the longest enduring members of the team, eventually forming the West Coast Avengers. He was also cast as an original Avenger in the MCU’s Avengers. Scarlet Witch and Quicksilver also would be featured in Avengers: Age of Ultron.

#9 The Ultimates

In 2002, Mark Millar and artist Bryan Hitch came up with the Ultimates, a modern re-telling of the origins of Earth’s Mightiest Heroes. The 13-issue series featured more mature themes and modernized art work. Bryan Hitch described his art as “widescreen, cinematic compositions,” and expressed an interest in taking the story to the big screen. Nick Fury was even re-designed with his new appearance based of actor Samuel L. Jackson.

The Ultimates did end up serving as the primary inspiration for the MCU’s Avengers. Samuel L. Jackson was cast as Nick Fury, and the rest was history. This is a series worth going back to, or reading for the first time. The characters are much more flawed than the classic Earth-616 Avengers.

#8 Behold the Vision

The introduction of Ultron was one of the most important villain debuts in Marvel comics. Not long after his first appearance, Ultron created the Vision as another weapon to use against the Avengers. His two-part story started in Avengers #57, and served as a precursor to bigger things.

Vision turned on Ultron soon after being unleashed upon the Avengers. This story dives deep into Vision’s psyche, exploring his humanity, and his attempts to reject the trauma brought on by the sins of his creator, Ultron. Vision became one of the mainstay members of the Avengers following this story. The traumatic relationship he and Ultron shared also bled into future Avengers comic books, as well as the movie, Avengers: Age of Ultron.

#7 Captain America joins the Avengers

Perhaps the most important moment in Avengers comic book history was the re-introduction of Captain America in Avengers #4. The character hadn’t been heard of since the 1950’s, and those stories were retconned as being a completely different character. Steve Rogers hadn’t actually officially been seen since 1945, when he was frozen in the North Atlantic Ocean. The Avengers discovered the man out of time, and he eventually became the most important member of the team’s entire history, serving as the heart and soul of the Avengers.

In the MCU, Captain America was dubbed The First Avenger, and served as the final piece to the formation of the Avengers, much like he was in the comic books.

#6 Ultron Unlimited

Ultron is one of the Avengers’ most dangerous enemies, and has been a part of some of the best stories ever told in the publication’s history. In a story told decades after the character’s debut, writer Kurt Busiek added a new level of depth to the character’s history. A dark revelation is made that Ultron’s brain patterns are actually based off of his creator, Hank Pym, making him basically the incarnation of the darkest part of Pym’s brain. The story involved the Avengers facing off against a vast Ultron army. This storyline served as inspiration for the character’s MCU debut in Avengers: Age of Ultron.

#5 Kang Dynasty

Kang Dynasty is an absolute massive storyline spanning 16 issues, starting in Avengers #41 (Volume 3). Kang arrived on Earth, claiming to be its “protector.” He and his son then launched a massive takeover of the entire planet, including destroying the UN headquarters, and convincing many of Earth’s villains to help him by promising them part ownership of the conquered planet. The Avengers were forced to scatter in order to deal with the growing threat, and Captain America faced off against Kang in an epic final battle.

Kang is one of the most well-known Avengers’ villains who has yet to debut in the MCU. Rumors are this is to change soon, as the MCU has plans for introducing the character soon.

#4 New Avengers: Breakout

While not on this list, Brian Michael Bendis’ Avengers: Disassembled storyline injected new life into the series by destroying the Avengers as we knew them. Several characters were killed or changed forever following this story. What emerged from the chaos was the ‘New Avengers.’

In New Avengers: Breakout, several heroes gathered at the Raft; a maximum-security supervillain prison that had been completely shut down after an attack from Electro. Former Avengers Captain America and Iron Man were joined by a ragtag group of heroes in order to quell the uprising, eventually forming the New Avengers. This story reinvigorated characters such as Spider-Woman and Luke Cage by bringing them into a major storyline that ended up spawning the Civil War, Secret Invasion, and the Siege of Asgard.

#3 The Korvac Saga

The Korvak Saga was written back in 1978 by Jim Shooter, and still serves as one of the best and most tragic stories ever told in the pages of the Avengers. Michael Korvac was a man from an alternate reality in the 30th century, who was made into a Cyborg by an alien race. After gaining God-like powers from the Power Cosmic, Korvak remade himself into a human named “Michael.” he began to alter reality in Earth-616, with the intention of creating a perfect Utopia. However, he was opposed by the Avengers. Without spoiling too much, the end of this story is bittersweet, as not everything was as it appeared.

Korvac is seen as one of the only beings powerful enough to challenge the Elders of the Universe, with the other being Thanos.

#2 Avengers Under Siege

Unlike most of the more popular stories involving the Avengers, the events of Avengers: Under Siege had more to do with the opportunism of “lesser” villains, as well as the interpersonal relationships of members of the team coming to a head. Baron Helmut Zemo formed the Masters of Evil, a group of over a dozen supervillains with the intent of completely overwhelming Earth’s Mightiest Heroes with sheer power. The multi-issue event began back in Avengers #270. This event rocked the Avengers to their very core, thinning the lineup down to one of its weakest points in history.

Baron Zemo’s actions during this event closely mirror much of what happened in the MCU movie Captain America: Civil War, where Zemo manipulated events surrounding the Sokovia Accords in order to get revenge on the Avengers.

#1 The Kree Skull War

Without a doubt, the single biggest Avengers story of all time is the Kree-Skrull War. Spanning several issues, and featuring an enormous cast of heroes, this mega-event was the culmination of the seemingly never-ending war between the Kree Empire and the Skrulls. The story was certainly galactic in scale, but it also dove into political territory that was relevant for the early 1970s. The story began in Avengers #89, and tackled subjects such as fear mongering by public officials and the media. Both the Kree and the Skrulls appeared in the MCU film Captain Marvel, which explored an alternate version of the war.