The Best Avengers Villains Who Have Fought Earth’s Mightiest Heroes

As a kid, I was terrified of Venom and Carnage, and for good reason. Although they have yet to meet with the Avengers in the MCU, the race of symbiotes known as the Klyntar could pose a real threat to Earth’s mightiest. In Mighty Avengers, Doctor Doom hit New York with a synthesized version of the symbiotes’ bond, Venomizing Spider-Man, Doctor Strange, and Wolverine, among others. In Marvel’s 2017 Spider-Man animated series, Venom summoned a cabal of Klyntar to infect New York City once again, taking down Iron Man, Captain America, Thor, Hulk, and Captain Marvel, among others. Spidey ultimately saved the day, but not before he said what we were all thinking: “Anyone know who we call when we need to be saved from the Avengers?”

Loki made his MCU debut early on in Phase One, acting as the primary antagonist for the first Avengers film and a real thorn in Thor’s side during his first solo outing. In the comics, the Norse God of Mischief has been around almost as long as his brother, and, like his MCU counterpart, he’s not always all bad. But when Loki wants to, he can cause plenty of problems for the Avengers. His magic makes him a formidable opponent, but when you add in his powers of suggestion — which can be used across great distances — and his utter disdain for dying, well, the world’s most powerful superheroes have got a real problem on their hands.

Speaking of tricksters, let’s talk about Mephisto. He’s been the source of endless memes since the MCU limited series began running on Disney+, but if you haven’t paid much attention to the Marvel Comics, you might not know who this devilish figure really is. Aside from appearances in both Ghost Rider films — fitting, since he’s the guy who created Ghost Rider in the first place — the ultra-powerful lord of Hell hasn’t gotten much screentime over the years. A 1987 run of four limited series saw Mephisto face off against the Avengers, the Fantastic Four, X-Factor, and the X-Men. Because he delights in tormenting souls and manipulating sacred timelines — and because he’s quite nearly all-powerful — he’s one of the best Avengers villains the MCU could introduce in Phase Four.

If there’s one thing we can learn from comic books, it’s that what you create may ultimately destroy you. Case in point: Ultron. Hank Pym designed this sentient robot, only to have it immediately turn against him. (It’s sort of a Frankenstein’s monster situation…if the monster had had no capacity to love. And had been, you know, a robot.) Now the biggest downside to creating a sentient robot who wants to eradicate humanity is that that robot can upgrade himself. And boy, does Ultron get some upgrades. The most insidious gadget he has is his encephalo-ray, which gives him full control over people’s minds, from making sleeper agents to rendering his victims comatose. Did I mention he can survive without a body, as nothing more than a radio signal floating through space? Yeah, this is one robot overlord you may not want to welcome.

The king of the Dark Elves, Malekith has been a frequent foe of Asgard, ever since his 1984 introduction to Marvel Comics. Malekith’s superhuman strength, speed, agility, and durability put him on par with many of the Avengers. His healing factor and magical capabilities give him an edge over many of Marvel’s finest, however. In The War of the Realms, Malekith declared war on Midgard, and it took more than just the Avengers to put him down. Deadpool, Venom, Lady Sif, Iron Fist, Shang-Chi, Daredevil, Namor, the Dora Milaje, and many more all showed up to kick some Dark Elf ass. Malekith has died and reappeared in the comics before, so there’s a chance we could see him again in the MCU, now that we’ve met most of his War of the Realms adversaries.

Oh, M.O.D.O.K. When a guy names himself Mental Organism Designed Only for Killing, you know he means business. Lab technician George Tarleton transformed into M.O.D.O.K. after an A.I.M. experiment designed to turn him into a human computer went horribly wrong. His enlarged head and weakened body necessitate the use of a mobility device: his Doomsday Chair, which he kits out with weaponry. M.O.D.O.K.’s most powerful weapon is his mind, however. The villainous supergenius is not only able to mind-control his victims and hit them with psionic blasts, but he also concocts nefarious, over-the-top schemes for Captain America and the other Avengers to thwart.

Norman Osborn’s turn as Green Goblin is iconic, but when he was at his most dangerous, he didn’t hide behind a mask. In the midst of the Secret Invasion storyline — which is coming soon to the MCU — Osborn took over S.H.I.E.L.D. and cast a group of villains as the Avengers themselves. Always willing to play both sides, Osborn also headed up The Cabal: a league of supervillains that included Doctor Doom and Loki. As part of his work with the so-called Dark Avengers, he styled himself as Iron Patriot — think Iron Man’s suit, but Cap’s patriotic flair — to fight crime, leaving the real Avengers to regroup and formulate a plan to take him down. There’s already been some speculation that the MCU would bring Osborn’s Dark Avengers into play, and the potential revival of the Green Goblin himself in Doctor Strange and the Multiverse of Madness only makes that move seem more likely.

The primary antagonist of the MCU’s first three phases, Thanos had a pretty decent run on screen. Marvel Comics fans know that it’s hard to keep the Mad Titan down, however. With his ability to live on cosmic energy alone, and his pesky habit of getting reincarnated at the most inconvenient moments, Thanos comes by his place in the top-5 best Avengers villains honestly. I seriously doubt he’ll make his return to the MCU anytime soon, but comics readers can expect to see his purple mug again…and again…and again.

Kang recently made his MCU debut on Disney+’s Loki to great acclaim, and it’s easy to see why. Born far in the future as a descendant of Reed Richards and/or Doctor Doom, Nathaniel Richards began styling himself as Kang when he conquered the first of many worlds. His time-traveling abilities give him the power to alter the past, present, and future, but doing so creates other versions of himself in myriad parallel realities. Those variants don’t always play nice, but that doesn’t stop the Kangs from frequently winding up on the Avengers’ good side, when the mood strikes them.

There’s just no one quite like Wanda Maximoff. What she lacks in physical strength, she more than makes up for with her devastating magical abilities. By harnessing the powers of chaos, Wanda can make dreams come true and force her enemies to live in their nightmares in perpetuity. Much like her MCU counterpart, the Scarlet Witch of the Marvel Comics made her own reality, born out of her grief over losing her twin sons, in House of M. Although she frequently collaborates with the Avengers, becoming one of their most powerful allies, Wanda has also presented them with some of their hardest challenges.

As far as the best Avengers villains go, it’s impossible to beat Galactus. No, really. He’s impossible to beat. I mean, how else do you describe a supervillain whose death would destroy you? And not just you, but all the yous in all the Universes to come? Galactus eats whole solar systems for breakfast, but he’s not evil. He just is. Every planet he eats becomes fuel for his inevitable death and rebirth: a new Big Bang that will usher in the dawn of a new cycle through time. Sure, the Avengers have to put Galactus in his place every so often, but they can’t kill him — without reviving him, that is — unless they want the Universe to never be remade again. Thanos might describe himself as “inevitable,” but Galactus — and possibly Galactus only — is truly worthy of such a title.