The Avengers are one of the most famous teams in all of pop culture. Since Stan Lee introduced the world to the Earth’s Mightiest Heroes, the group has become an iconic assembly of characters. Members like Captain America, Iron Man and Scarlet Witch fill the team’s roster with some of the most powerful heroes in the Marvel Universe, or the MU. Naturally, when the Marvel Cinematic Universe (the MCU) launched, the Avengers were at its center. These films have made Iron Man and his teammates famous to even the most casual fans. Through decades of prosperity, writers have needed to match the might of the heroes with equally challenging villains. Sure, some of these antagonists are one-offs but, for the characters that keep coming back, writers needed to make them as powerful as the heroes.

Many of these villains have made the leap to the MCU. Unfortunately, while there are some exceptions, their live-action counterparts haven’t lived up to their reputations. When considering power, we considered that it can present itself in many forms. Some of these characters have superhuman abilities that allow them to go toe-to-toe with Thor, Black Panther and their teammates. Other villains have tactical and strategic expertise that allows them to indirectly challenge these heroes with the manipulation of foot soldiers. Regardless of the source of their strength, we’ve decided to rank the most powerful Avengers villains. From the Red Skull to Thanos, the Avengers have faced some fearsome foes over the years. Read on to see who we ranked as the most powerful of them all.

16 VIPER

Viper

Viper, or Ophelia Sarkissian, is one of the most vital people in Hydra, so she certainly belongs on this list. Sarkissian’s brilliant plotting has helped keep the organization afloat, even when the group seems to be on its last legs. Viper also had a key role in the lead-up to "Secret Empire", as she was on Elisa Sinclair’s Hydra High Council.

Even outside of her traditional allegiance with Hydra, Viper has connections all throughout the criminal underworld. Her expertise and abilities in the field are highly valued. Sarkissian may not have superpowers but she is still a dangerous threat to the Avengers.

15 BARON ZEMO

Helmut Zemo

Baron Zemo, or Helmut Zemo, is the latest in a long line of barony. Helmut is arguably the most famous and he’s had the most staying power -- he’s been antagonizing Captain America since 1973 (though his first full appearance didn’t come until 1982). Zemo is one of the many Marvel villains that just keeps coming back. Helmut is a genius and he is infamous for his abilities as a tactician.

Helmut also has access to the Moonstones, which give him incredible powers, including the manipulation of light and energy. Zemo was a main character in "Secret Empire" and, since then, has continued his efforts to restore Hydra to its powerful self.

14 RED SKULL

Red-Skull-Marvel-Comics

Red Skull is one of the most dangerous, and outright evil, characters in the history of comic books. He’s been Captain America’s nemesis since 1941 and he keeps finding ways to torment the First Avenger. Johann Schmidt unleashes weapons of mass destruction on a regular basis and the Avengers can never tell where he’ll strike next.

In recent years, Schmidt has stolen Professor X’s body and fused his mind with the powerful mutant. With these new abilities, Red Skull launches a new reign of evil, including being directly responsible for "Secret Empire". Time and again, Schmidt has proven that he is a menace to the Avengers.

13 NORMAN OSBORN

New-Avengers-Norman-Osborn

We could write a whole list of the worst things Norman Osborn has done to Spider-Man. The former Green Goblin’s villainous schemes are practically unrivaled, but Osborn has frequently strayed from his conflict with the Web-slinger in favor of larger goals.

Osborn manipulated the entire world, which is why he was handed the keys to the kingdom after "Secret Invasion". Subsequently, “Dark Reign” saw Osborn tarnish the legacy of the Avengers by launching his own corrupt version of the team. Osborn eventually fell from grace but it’s certainly possible that he’ll position himself to regain some power in the future.

12 SCARLET WITCH

scarlet witch hex

Most of the time, Scarlet Witch is a hero, fighting alongside the Avengers and she’s a valuable member of the team. However, Wanda Maximoff occasionally displays some villainous tendencies. Whenever she does, the consequences are dire.

In the controversial “Avengers Disassembled” storyline, Maximoff antagonizes her former allies and fractures the team beyond repair. Shortly thereafter, in "House of M", Wanda warps reality and depowers the vast majority of the mutant population. Maximoff can also be a threat unintentionally and in "Secret Empire", she was brainwashed by Hydra. The organization then used her as one of their “Avengers.” When Maximoff breaks bad, the world itself is at risk.

11 GRAVITON

Graviton displays his powers

With the ability to manipulate gravity, Graviton is definitely one of the most powerful villains the Avengers have faced. Graviton, or Franklin Hall, can fire blasts, project force fields and, of course, he can fly. Hall’s powers also allow him to hold his enemies in stasis, which can nullify any hero’s attempt to stop.

Agents of S.H.I.E.L.D. brought Graviton to the small screen and the show accurately captured the character’s sheer power. In the show, Glenn Talbot absorbs gravitonium and instantly becomes the most mighty character on the show. Talbot becomes convinced that he can stop Thanos’ invasion, and his delusions of grandeur are his ultimate downfall.

10 ANNIHILUS

Fantastic Four villain Annihilus drawn by Jim Cheung.

It’s surprising that Annihilus hasn’t gotten more recognition. In "Annihilation", under the leadership of the Lord of the Negative Zone, the Annihilation Wave nearly decimated the universe. However, given that this event overlapped with "Civil War", it makes some sense that this cosmic tale didn’t receive as much attention but, eventually, Annihilus made the Avengers take notice.

The villain made another attempt to conquer the universe and, when the Earth’s heroes tried to stop him, they failed. Only the intervention of the “Above-All-Others” stopped the one known as the Living Death That Walks. The All-New, All-Different Avengers stopped Annihilus again but the, sooner rather than later, the villain will likely return.

9 MODOK

MODOK looking menacing in Marvel Comics.

MODOK has been a menace for over 50 years, as the character continues to find ways to villainize the MU. The original MODOK, George Tarleton, was dangerous because he had superhuman intellect and psychic powers that were augmented by his technology. A newer version of the character, MODOK Supreme, debuted in 2011.

Unlike its predecessor, this iteration isn’t confined to a human body. Instead, this version is a supercomputer with a clone of Tarleton’s brain at its center. MODOK Supreme, at times, has maintained Tarleton’s partnership with A.I.M. but it has also aligned with S.H.I.E.L.D., proving that this version can have a heroic side. Still, MODOK remains one of the Avengers’ most powerful villains.

8 ULTRON

Hank Pym bonded with Ultron

What do you get when you give genius-level intellect to artificial intelligence? Ultron is the product of this combination. With several impressive abilities, such as super-strength, super-speed and mind control. These powers would make Ultron a dominant hero but unfortunately, he’s one of the most evil villains in Marvel’s history. As a self-repairing and replicating unit, Ultron keeps finding ways to come back better (or worse, depending on your perspective) than ever.

This AI displayed its might in the comic book version of Age of Ultron, when it conquered the world. The MCU version didn’t quite match his comic counterpart but the Avengers still had some difficulty defeating him.

7 LOKI

Loki

It’s ironic to say that Loki is one of the most dangerous villains that the Avengers have faced. After all, Loki inadvertently caused the group to assemble in the first place. But Loki Odinson is a trickster god, which has allowed him to execute various nefarious plots. Unfortunately, for the Earth’s Mightiest Heroes, they’re usually at the center of these schemes.

Beyond his schemes, as an Asgardian, Loki is a powerhouse. He has superhuman strength, the ability to fire energy blasts and an assortment of other abilities. Plus, he can shapeshift and conjure illusions, and these skills make his manipulative plots, at times, untraceable.

6 KORVAC

korvac-saga-display

Korvac is one of the most underrated villains in the MU. With access to the Power Cosmic, he became practically invincible. It took the combined effort of the Guardians of the Galaxy and the Avengers in “The Korvac Saga” to defeat a being that is sometimes called the Enemy.

The villain preserved himself even after the heroes of Earth defeated him -- Korvac sent his essence through time so he could inhabit new hosts. These efforts were ultimately futile but Korvac was one of the strongest threats Marvel’s heroes had faced. Even without the Power Cosmic, Korvac could weaponize any form of energy that he absorbed.

5 THE SKRULLS

With other characters on this list, we tried to focus on an individual. The Skrulls are an exception, as it’s difficult to pinpoint members of this race that are more powerful than the others. The most dangerous thing about the Skrulls, as we learned in "Secret Invasion", is their strength in numbers. They secretly replaced many of the Earth’s heroes and nearly took over the world.

With alien imposters in their midst, the Avengers had never been so compromised. Power comes in many forms; the Skrulls had the ability to capitalize on a fractured superhero community and bring the world to its knees.

4 KANG

kang

Kang the Conqueror has a long, winding history that can confuse even the most knowledgeable comic book fans. At times, he’s been Nathaniel Richards, Rama-Tut and Immortus. Despite the character’s murky past, it’s clear that he is one of the most impressive villains that the Avengers have ever faced.

Kang is a genius with the ability to time travel. He also has access to advanced technology, which, paired with impressive combat skills, makes him a formidable adversary. He has been going after the Avengers since 1964 and he will likely continue to be on the short list of villains that could defeat the Avengers.

3 DOCTOR DOOM

Body By Doom: 20 Weird Secrets About Dr. Doom's Body And Armor

Doctor Doom is one of the most famous villains in Marvel history. Though he is often linked to the Fantastic Four, Victor von Doom has dueled with the Avengers many times throughout the years. Doom is like a villainous Tony Stark with his technological genius. Plus, he’s the leader of a nation (Latveria) and a master of magic. Put it all together and you get an incredibly powerful antagonist that strikes fear into the strongest Marvel heroes.

In recent years, Doom shifted away from his life of villainy; Infamous Iron Man showcased a repentant Doom that wanted to help people. But, with the return of the Fantastic Four, it seems that the evil Doctor is back to his usual ways.

2 GALACTUS

galactus

Galactus, or Galan, has softened (somewhat) in recent years but, once upon a time, he was the most dangerous villain in a universe chock-full of evildoers. Galan is a cosmic entity that feeds on planets; he was called the Devourer of Worlds for a reason. Additionally, Galactus wields the Power Cosmic, which gives him a plethora of powers including telepathy, telekinesis and the ability to transmute matter.

The giant, armor-clad being debuted as a Fantastic Four villain but he quickly became a threat to the World’s Mightiest Heroes. On several occasions, Galactus has given the Avengers all they can handle, so they should be relieved that Galan has become the Lifebringer.

1 THANOS

Thanos holding Captain America's skull in Marvel Comics

Thanos has been a thorn in the Avengers’ sides since 1973. The Mad Titan was an impact player right away but he took things to a different level in the Infinity Gauntlet story. Thanos collected the Infinity Stones and became the most powerful being in the MU. The stones gave this power-hungry villain mastery of time, the soul, space, the mind and reality itself.

With the ability to shape reality as he saw fit, Thanos arguably became the most dangerous antagonist the Avengers had ever faced. It’s only fitting that the native of Titan has become the MCU’s big bad; once again, Thanos’ ability to wreak havoc on the Avengers is unparalleled.