A good superhero story is incomplete without a worthy villain. Throughout the Marvel Cinematic Universe, there have been a plethora of villains who have traded blows with Earth's mightiest heroes. From intergalactic conquerors to relatives gone rogue, there is no shortage of iconic antagonists who push the audience's favorite heroes to new levels of power.
Some of them, like Thanos or Loki, have character arcs that span several films in the MCU, while others only get one opportunity to showcase their villainous potential. These ten villains make a big impact on the heroes they face just from being in one film, and they're backed up by some pretty incredible performances. Spoilers ahead!
10 Obadiah Stane
All the way back in 2008, Jon Favreau's Iron Man kicked the MCU off with a bang. For a younger, more self-centered Tony Stark, no character was better to force him into superheroism than Obadiah Stane. With a brilliant performance by Jeff Bridges, no Marvel fan can erase his iconic quote from their heads: "Tony Stark was able to build this in a cave! With a box of scraps!"
Of course, Stane is referring in that line to his attempted assassination of Stark, after joining forces with the mysterious Ten Rings organization to overthrow the billionaire playboy as CEO of Stark Industries. Few MCU villains can boast that they are scarier outside their giant weaponized suits than they are inside them.
9 Ultron
When Tony Stark's artificial intelligence program-gone-wrong first appears in Avengers: Age of Ultron, he easily becomes one of the greatest MCU villains of all time with his chilling speech about feeling like a puppet attached to strings. As the movie progresses, Ultron proves to be one of the Avenger's greatest threats as he planned for human extinction to make way for technology's conquest.
Thanks to a bone-rattling vocal performance by James Spader, Ultron comes nearly close to achieving his goal before being stopped by the Avengers. Along the way, the Avengers recruited Ultron's former teammates, Wanda and Pietro Maximoff, as well as Ultron's own synthetic creation Vision. While his plan was thankfully never seen through, his actions eventually tear the Avengers apart in Captain America: Civil War.
8 Ego
In Guardians of the Galaxy Vol. 2, Kurt Russell portrays this ruthless Celestial (who is albeit a far cry from the Celestials later seen in 2021's Eternals). Ego introduces himself to the Guardians after hearing of Peter Quill's encounter with the Power Stone, surmising that Star-Lord is the son he sired with Peter's mother on Earth in the 80s.
While Ego presents himself as a welcoming host for Peter and his friends, the Guardians soon discover Ego's true intentions to transform various planets into extensions of himself. After Peter learns that it was Ego who killed his mother by planting a brain tumor in her head, he too turns against his father and successfully destroys him.
7 Hela
While Taika Waititi's Thor: Ragnarok is for the most part a light-hearted, comedic adventure vastly different from the previous two Thor movies, Hela proves to be a vicious and dark adversary for Chris Hemsworth's Thor. As the firstborn child of Odin, Hela enters Thor: Ragnarok with style, destroying Thor's hammer Mjolnir and sending Thor and Loki on a collision course to the planet Sakaar.
Thor manages to return to Asgard to confront Hela, and their ensuing fight results in Thor losing an eye before retreating with the "Revengers" and helping all the Asgardians escape. The only thing that can defeat Hela at this point is the summoning of Surtur, a Fire Demon who destroys Asgard — and Hela with it.
6 Erik Killmonger
Making his appearance in the box office smash Black Panther, Erik Killmonger might go down in history as one of the MCU's greatest supervillains. Erik is a former Navy SEAL who plots his revenge against Wakanda for the murder of his father, N'Jobu. When Erik finally faces off against Chadwick Boseman's T'Challa, he defeats him and claims the Throne of Wakanda, as well as the title of Black Panther.
T'Challa returns to stop Erik's plans to arm oppressed Africans around the globe. In his heart-wrenching death scene, Erik reminds T'Challa of all the good Wakanda could do with its resources. This impact Erik has on T'Challa leads him to volunteer Wakanda's plethora of vibranium around the world.
5 Mysterio
Before masquerading as a superhero from an alternate universe, Mysterio was Quentin Beck, a scientist fired by Tony Stark for being unstable. With his team of disregarded Stark Industries employees, Quentin successfully tricks the naive Peter Parker into giving him E.D.I.T.H., an artificial intelligence system gifted to Peter by the deceased Tony.
When Peter later discovers Quentin's scheme, he disrupts a simulated Avengers-level threat to steal back E.D.I.T.H. However, he's too late to stop Quentin from recording a doctored video exposing Peter's identity to the entire world, leading to the multiverse-rippling events of Spider-Man: No Way Home. If only Peter kept E.D.I.T.H. to himself, then life would be looking a lot different for the friendly neighborhood hero.
4 Karli Morgenthau
Appearing in the Disney+ show The Falcon and the Winter Soldier, Karli is a terrorist who, with a group called the Flag Smashers, seeks to create anarchy after being displaced from her home following the return of people who disappeared during the Blip. She nonetheless attracts the attention of Sam Wilson and Bucky Barnes, as well as the U.S. government and John Walker.
Sadly, Karli's stubbornness deters her from reasoning with Sam. She's eventually killed by Sharon Carter, her former employer, and dies in Sam's arms. Her legacy lives on, however, as Sam defends her honor to the leaders of the Global Repatriation Council, convincing them to enact laws that would further Karli's cause.
3 Xu Wenwu
The leader of the Ten Rings, Wenwu is a centuries-old conqueror who gave up his path to power to start a family with Ying-Li. He later became the father of Shang-Chi and Xialing. After Ying-Li is killed by a rival crime syndicate, Wenwu trains his children to become assassins, looking to avenge his wife's murder.
Eventually, Shang-Chi teams up with the ancient city of Ta Lo to stop Wenwu from waging war against them, believing they can resurrect his wife. Wenwu and Shang-Chi fight, before Wenwu sacrifices himself to save Shang-Chi from the Dweller-in-Darkness, a Soul Eater he accidentally releases. With an incredible performance by Tony Leung, Wenwu is one of the MCU's most empathetic and complex villains to date.
2 Ikaris
The biggest twist in 2021's Eternals comes when the group's de-facto leader, played by Richard Madden, turns against his family. As a loyal soldier to the Celestial Arishem, Ikaris attempts to stop the other Eternals from preventing The Emergence, a birthing process for new Celestials that will result in the destruction of Earth.
Ikaris fights the Eternals, eventually giving up when he can't bring himself to kill his former lover, Sersi. To avoid judgment from Arishem, Ikaris lives up to his name and flies into the sun. Since he's a synthetic creation of Arishem, Ikaris could return to the MCU, but he won't be the same one who spent thousands of years on Earth.
1 Kro
Kro appears in Eternals as the leader of a pack of Deviants who were frozen in ice for thousands of years. After killing both Ajak and Gilgamesh, Kro absorbed their powers and evolved. With his newfound sentience, he realizes the slaughter of Deviants by Eternals for millions of years and vows to seek justice.
Kro, whose evolved form is portrayed by Bill Skarsgård, eventually disrupts the Eternals' climactic fight with Ikaris. However, he's eventually sliced into pieces by Thena as revenge for killing Gilgamesh. Though his quest for vengeance was short-lived, he makes quite the impression during his vicious fights against the Eternals.
