The Avengers are Earth's Mightiest Heroes. A collection of gods, geniuses, and master combatants, the Avengers are set to take on any threat to the Marvel Universe. At least, that's what the Avengers believe. Despite their assembled power, the Avengers still find themselves in over their heads quite often.
The Avengers' tendency to get into trouble takes a variety of forms. Sometimes, its due to a lack of understanding of a particular situation and the team requires others to help explain it to them. Other times, the combined powers of the Avengers just can't compare to godlike opponents. Try as they might, sometimes the Avengers need bailing out.
10 Bloodties
In little-remembered 90s Avengers/X-Men crossover Bloodties, the two teams converged on the apartheid nation of Genosha where a strict segregation system between mutants and humans was enforced. The Avengers' mission: retrieve Quicksilver's kidnaped daughter from X-Men villain Fabian Cortez.
However, the Avengers got far more than they bargained for in the conflict. Upon their arrival, Genosha's once-enslaved mutant population had risen up to start a civil war. As the rebels fought the government, former Acolytes of Magneto like Cortez and Exodus made power plays against groups like the Genoshan Magistrates and even the UN. As the fight continued, the Avengers proved themselves politically out of their depth.
9 Secret Wars Vol. 1 #11
The initial Secret Wars was created for kids, but the series still racked up a high body count. As the gathered heroes and villains of the Marvel Universe fought amongst themselves and each other, Doctor Doom stole the omnipotent power of the Beyonder.
When the heroes learned of this, Captain America led the Avengers, X-Men, and Fantastic Four against Doom. Doom asked the heroes to join him. The heroes said no and Doom obliterated the assemblage in an instant. The group was only revived by the sacrifice of a healer the group had met, bringing the dead group back from eternity.
8 Onslaught
When the Avengers and X-Men cross over, someone always gets hurt. Sometimes, it's the heroes themselves. Such was the case in mid-90s event Onslaught, when the teams first sought to identify and later destroy the malevolent entity. Even at the end of the event, the heroes remained a step behind the villain.
Onslaught manipulated the heroes for a long time, including mind-controlling the Hulk to battle the X-Men. When the Avengers joined with the X-Men and Fantastic Four in final battle against Onslaught, the Avengers launched themselves into Onslaught's energy form. Though the move beat the villain, it also removed the human team from Earth 616.
7 Civil War Vol. 1 #4
While the mainstream Avengers often make it out of situations alive, the less-popular members of the team are not always as lucky. Superhero slugfest Civil War saw the Avengers split down the middle when Captain America led half of Marvel's hero community against Iron Man's government forces.
In issue #4 of the crossover, Iron Man, Yellowjacket, and the Pro-Registration side unleashed their Thor clone on their opponents. The clone quickly went out of control, gravely injuring many of the Anti-Registration heroes and even killing Bill Foster, AKA Goliath. Whether Pro- or Anti-Superhero Registration Act, all Avengers were outmatched by the rogue experiment.
6 Inferno
Before the Avengers were the superstars of the Marvel Universe, the X-Men held that honor. For decades, the Avengers, Fantastic Four, and rest of the Marvel Universe were dragged into various X-Men-centric crossovers, including 1989's Inferno. As the Avengers fought through demon-infested New York, they were left scratching their heads.
In addition to the demonic forces of Limbo completely overrunning New York, X-Men villains Nanny and the Orphanmaker kidnaped Franklin Richards, son of Sue and Reed Richards. A beleaguered Captain America assembled a rough team of Avengers and attempted to rescue the child while evading the horrors of a crossover they barely understood.
5 Secret Avengers Vol. 1 #20
While the Avengers often face global-scale threats, the smaller-sized threats remain dangerous. The second iteration of the Secret Avengers changed the team from a group of rebels to a more black-ops version of the Avengers who would routinely face and eliminate some of these smaller-scale threats.
However, a routine mission for the team saw the entirety of the group (except for Black Widow) killed by laser fire. Black Widow was able to avert the team's death using time travel, but the ease with which the team was laid low shows that even mundane threats can sometimes outmatch the Avengers.
4 What If...? Vol. 1 #66
Alternate realities, at least the ones visited in What If titles, are not generally kind to Marvel's heroes. The series often examines what would happen if events in the Marvel Universe transpired differently, including when Rogue and the new Brotherhood of Mutants first battled the Avengers.
In the fight, Rogue absorbs the powers of Thor and later kills Hawkeye, Jocasta, and Vision, soundly defeating the Avengers. Rogue fully outclasses the group and later destroys the Brotherhood, too. Though Rogue then joins the side of good, the Avengers of this reality were fully out of their depth in this fight.
3 Avengers Disassembled
Sometimes, danger comes from the Avengers themselves. Following an off-color remark from the Wasp, the Scarlet Witch began to struggle with her grasp of reality and subconsciously began to attack the Avengers. The threats against the Avengers struck hard and fast, a combination of old friends and enemies attacking the team.
When the dust settled, several high-profile members were dead and the rest of the team disgraced, disillusioned, or disbanded. Many years later, both the Scarlet Witch and the team would recover from the events of Avengers Disassembled, but the Avengers were fully destroyed first.
2 "The Korvac Saga"
Sometimes, the Avengers being outclassed makes for their best stories. That includes the classic "Korvac Saga," a tale written primarily by Jim Shooter and drawn by George Pérez. The two legendary creators pitted the Avengers and Guardians of the Galaxy against an all-powerful human computer named Korvac.
Though the groups fought valiantly, they did not stand a chance against Korvac. The raging superhumans were eliminated with a thought. Even as Don Blake, Thor's doctor alter ego, sought to save their lives, the teams were only truly restored to life because Korvac wished it so.
1 The Infinity Gauntlet
Thanos's acquiring of the Infinity Stones was a big deal in the comics as well as the MCU. When the Mad Titan became cosmically empowered in The Infinity Gauntlet, he first eliminated half of the life in the universe. Following that, he defeated an assemblage of remaining Earth heroes like Captain America, Thor, and She-Hulk.
Even the assembled cosmic forces of the universe are bested by Thanos. Thanos loses when Nebula grabs the glove from him, an act that in turn allows Adam Warlock to beat Thanos and Thanos decides to take up a life of quiet contemplation. Though critical in the story, the Avengers are almost a non-factor in deciding how it ends.