Perhaps the most famous defeater of the Avengers on this list, Thanos is another of the Avengers' more dogged foes. Even without the Infinity Gauntlet, Thanos has proven himself to be a hugely powerful threat, often taking on entire teams of Avengers at once.
Blessed with the powers and long life of a god, Thor was undoubtedly the most powerful member of the initial version of the Avengers. Not only can he fly and transport between worlds, but he was also the only one capable of taking down Thanos, even after he had assembled all six Infinity Stones.
Spider-Man may be one of the strongest Marvel heroes around, but Captain America was still the best soldier alive. Cap's experience always beat Spider-Man's raw strength.
The invincible Iron Man may have the best and most well-built armor that can protect him from bullets or bombs, but a single strike from Wolverine can end his life.
Thanos's power, cunning, and years of experience have allowed him to outsmart and defeat some of the most powerful beings in the universe. All manners of beings have fallen before Thanos and while the Avengers are powerful, if Thanos really put his mind to it, he could end the Avengers at any moment.
Hercules / Zeus
He ranks above Thor here because he's technically the stronger of the two. In fact, he is considered by many authorities to be the physically strongest character Marvel has ever created. According to legend, he replaced Atlas in holding the sky on his shoulders.
Hulk. In terms of sheer physical strength, the Hulk could easily out-muscle Captain Marvel.
Captain Marvel is one of the most powerful Avengers who can defeat Captain America. Her superhuman strength, flight, and energy projection abilities make her a formidable opponent in battle.
Captain America may well be one of the greatest fighters in the Marvel Universe, but even years of combat experience and an unbreakable shield can't match Thor when it comes to sheer power.
2) Captain Marvel
She holds her own with Thanos in hand-to-hand combat for longer than Thor, Iron Man, or Steve Rogers, and takes down his enormous warship single-handedly.
Thor. Thor, the god of Thunder, was undoubtedly the most powerful member of the original Avengers. His power continues to grow in the Marvel Cinematic Universe.
Steve RogersCaptain America
Recipient of the Super Soldier serum, World War II hero Steve Rogers fights for American ideals as one of the world's mightiest heroes and the leader of the Avengers. America's World War II Super-Soldier continues his fight in the present as an Avenger and untiring sentinel of liberty.
Black Panther, real name T'Challa, is the King of Wakanda and the leader of the New Avengers.
In the aftermath of his failure, Thor had a new-found determination to kill Thanos and undo the Snap. The remaining Avengers converged on the Titan's home to find him wounded and the Infinity Stones destroyed. Seeking vengeance, Thor raised Stormbreaker and, with one fell swoop, beheaded Thanos.
Alex Summers aka Havok may not be as popular as his more famous brother, but he is easily one of the most powerful mutants in the Marvel Universe. Summers' powers exploit one of the Hulk's few weaknesses, allowing him to defeat the green behemoth with shocking simplicity.
Thor and Iron Man have mostly been friends over the years, but they have come to blows, most notably upon Thor's return after Civil War. Thor took exception to Iron Man's actions when he found out about them, especially Iron Man's use of a Thor clone, and the two came to blows. Thor beat Iron Man easily.
5 Scarlet Witch Is A Reality Warping Magic-User Who Outpowers The Highly Skilled Doctor Strange. Wanda Maximoff is one of the only superhumans in Marvel Comics who is considered to be a Celestial being due to her incredible superpowers.
Captain Marvel Was Just Beaten By Spider-Man's Most Dangerous Web Attack. Spider-Man can officially take down Captain Marvel - but his dangerous strategy involves shooting webs directly down her throat.
In the main Marvel Comics continuity, despite all her power, the Scarlet Witch could not stand next to god-like forces such as the Phoenix Force, Galactus, and the Living Tribunal.
When it comes to the most overpowered superheroes in the Marvel Universe, no one touches the power of Squirrel Girl. She has beaten anyone who crossed paths with her, and that is why Squirrel Girl has remained undefeated to this day.