Over the last fourteen years, the Marvel Cinematic Universe has presented its heroes with plenty of terrifying villains determined to wreak their havoc upon the world. The franchise shows no signs of stopping, adding new conflicts between hero and villain at a breakneck pace.
The heroes almost always emerge victorious from their clashes with the MCU's supervillains, but every so often, one particular Big Bad proves themselves, coming within mere inches of victory in their dastardly plans, with some even defeating their respective superheroes to accomplish their dark deeds.
Green Goblin, No Way Home
Though he is not an MCU villain in origin, Willem Dafoe's Green Goblin returned to once again wreak havoc on the life of yet another Spider-Man in the smash success that was Spider-Man: No Way Home. Throughout this event film, the Goblin proves why he is one of Spider-Man's greatest foes of all time.
Like many other superheroes' archnemeses, the Green Goblin doesn't necessarily function under a rigid formulated scheme. Rather, his plot consists entirely of corrupting the hero, something he very nearly succeeds in with Tom Holland's Peter Parker, who came within inches of murdering his helpless foe, only to be stopped by his seasoned multiversal counterpart.
Ultron, Age Of Ultron
Avengers: Age of Ultron may not be the fandom's favorite Avengers movie, but it does feature a fascinating villain in the artificial intelligence Ultron, voiced with the chilling cadence of James Spader. As he gains sentience, Ultron attempts to wipe humanity off the face of the earth, thus saving the planet itself.
In the climactic final battle of the film, Ultron manages to detach the small nation of Sokovia from the earth's crust, turning it into a meteor capable of wiping out all life on the planet. While the Avengers eventually stopped his plans, Ultron was successful in destroying much of Sokovia, as well as the territories surrounding it, causing plenty of havoc despite his ultimate failure.
Agatha Harkness, WandaVision
WandaVision introduced Marvel fans to a fun and engaging new villain in Katheryn Hahn's Agatha Harkness. Over the course of the series, Harkness infiltrated Wanda Maximoff's Westview Hex, becoming friends with the Avenger in order to steal the powers of the Scarlet Witch for herself.
In the final episode, Harkness exploits Wanda's love for her family, convincing her to give up her powers in order to save them. Though it appeared for a moment that Agatha would indeed gain all of Wanda's powers, she found herself deceived at the last moment, as the reborn Scarlet Witch instead cast the runes necessary to render Agatha helpless, thus defeating the wicked witch.
Dormammu, Doctor Strange
Though the primary villain for much of Doctor Strange was Kaecilius, the destitute former sorcerer of Kamar-Taj played by Mads Mikkelson, the bigger threat by far proved to be Kaecilius's master, Dormammu, ruler of the Dark Dimension, whom the wicked sorcerer attempted to summon to his own realm.
In the film's climax, it was clear that Doctor Strange was no match for the otherworldly force of nature, who indeed killed the Master of the Mystic Arts countless times. It was only by Strange's meddling with time itself that Dormammu relented. Even so, the king of Dark Dimension was not annihilated, and could perhaps return once more as a villain in Doctor Strange in the Multiverse of Madness.
Ikaris, Eternals
Ikaris was a member of mythologically-based superheroes known as the Eternals, who, after discovering the truth about their mission to Earth, attempted to stop the Emergence of the Celestial Tiamut from within the planet's core. Loyal to the Celestials, however, Ikaris desperately attempted to stop his comrades from saving humanity.
Thanks to Ikaris's meddling in the Eternals' plan, Tiamut was able to begin the process of the Emergence, with the Celestial's upper body protruding from the ground. However, halfway through the ordeal, the Eternal Sersi managed to harness the power necessary to turn the Celestial to stone, thus bringing to an end Ikaris's ultimate goal.
Thanos, Endgame
When the Mad Titan Thanos returned from the past to take on the Avengers in one last battle, his plans changed from his more altruistic goals from Infinity War, this time aiming to destroy the entire universe in favor of designing an entirely new one in his own image.
Despite the massive reinforcements that arrived to back up the Avengers, the final act of the battle came down to Thanos and Iron Man. The Mad Titan had the Gauntlet and all the stones necessary to accomplish his goals, only to learn too late that the Avengers had learned from their mistakes from fighting him the first time.
Surtur, Ragnarok
Cate Blanchett's Hela may have been the main antagonist of Thor: Ragnarok, but her plans unraveled far quicker than those of the evil being known as Surtur. Destined to destroy Asgard, Surtur awaited the moment when he would be summoned in the city of the gods to finally bring about Ragnarok.
In the third act of the film, Thor realizes that the only way to stop Hela is by allowing for the destruction of Asgard itself. To do so, Loki is sent to summon Surtur, who makes quick work of the golden city, bringing about Ragnarok as he had always been foretold to do. While he did accomplish his task, Surtur did fail to wipe the Asgardians out entirely, as a group led by Thor managed to escape the destruction.
Baron Zemo, Civil War
Certain men don't need superpowers in order to wreak havoc upon the world. Such was the case in Captain America: Civil War with main antagonist Helmut Zemo, who planned to rip the Avengers apart from the inside after his family was killed in the fallout of the Battle of Sokovia.
After ending up in prison for his crimes, FBI agent Everett Ross taunted Zemo for his failures, prompting the villain to ask if his plan had really failed at all. Indeed, though Zemo was brought to justice, his plot to destroy the Avengers succeeded, as Iron Man and Captain America had fallen out in a way that would leave the team fractured for the next seven years.
Mysterio, Far From Home
Jake Gyllenhaal's Mysterio followed in the tradition of competent Spider-Man villains who, despite their failings, ultimately succeed in making the life of Peter Parker just a bit harder. During his scheming in Far From Home, Mysterio attempts to strike a permanent and irreversible blow to his arachnid arch-nemesis, with some success.
Though Mysterio was seemingly killed after Spider-Man foiled his plot, the master illusionist had one more trick up his sleeve: revealing the hero's true identity to the world. This contingency plan proved to destroy Peter Parker's life for the next several months until he was ultimately able to reverse Mysterio's actions in the following film. Despite overcoming Mysterio's final plot, Peter still paid dearly for his return to anonymity.
Thanos, Infinity War
The primary focus of the first three phases of Marvel films was to set up the arrival of the Big Bad of the Infinity Saga: the Mad Titan Thanos. The villain didn't disappoint when he finally made his move in Avengers: Infinity War, ruthlessly tracking down each of the six Infinity Stones in his bid to destroy half of all life in the universe.
In a shocking twist that left audiences heartbroken, Thanos defeated the Avengers in each of their encounters, eventually completing the Infinity Gauntlet and snapping his fingers, wiping out fifty percent of all life. The universe was left to deal with the fallout of Thanos's actions for the next five years before the Avengers were able to bring back all who were lost in the Decimation, but not without permanent damage being done to the universe as a whole as a result of Thanos's crusade.