Proud, arrogant and the ruler of Latveria; Doom is an intelligent schemer and chief competitor with the Red Skull in the quest for world domination.
- Badass in Distress: During The Ambassador, when he's forced to go without weapons for the duration of the episode when speaking to the United Nations.
- Benevolent Boss: The Avengers in the alternate timeline where he conquered Earth showed practically no qualms about working for him (besides Natasha, who was kinda forced to marry him).
- Big-Bad Ensemble: He's the most recurring major villain outside the Cabal and is actively working against Skull.
- Chuck Cunningham Syndrome: Like Dracula, he hasn't been seen since season one.
- Day of the Jackboot: We get a good look at what New York City would be like if Doom had ruled it for a few years in Planet Doom.
- Demoted to Dragon: Doom actively averts this, vehemently refusing to follow Skull's lead.
- In Exodus, we learn that this was a very smart choice indeed.
- Diplomatic Impunity: Doom's a super-villain but he is also the legitimate head of state of a sovereign nation, which grants him some legal protection. The Avengers trying to find a way around this forms a considerable plot point in Ambassador.
- Don't You Dare Pity Me!: His reaction to Tony offering to assist in rebuilding the Destroyer destroyed area of Latveria, is to shock him, refuse, and tell the Avengers to get the hell off his land.
- Egopolis: He renames Earth Planet Von Doom after he conquers it and changes the Statue of Liberty to a statue of himself when he makes New York the capitol of his world empire.
- Emperor Scientist: Granted, he plays around with magic just as much as he plays around with technology.
- Enemy Mine: The Avengers, especially Cap, end up escorting and body-guarding him during his visit to the United Nations. Of course, Doom has ulterior motives.
- Even Evil Has Standards: For all that that he's an evil, power-hungry bastard, Doom is genuinely horrified when he sees the damage that he did to Latveria while wielding The Destroyer. Black Widow even notes this as the first sign that something isn't right with him: As much of a tyrant as he was, Doom never stooped to killing his own people.
- Evil Is Not a Toy: Invoked when he tries to summon and control the Midgard Serpent. Whether he would succeed in controlling him or not is left ambiguous at best. Later, it's shown that he did succeed in controlling the beast. However, he still went overboard with the Destroyer.
- Evil Overlord: He's the dictator and tyrant of Latveria.
- Evil vs. Evil: He's at war with HYDRA, AIM, and the Cabal, though as of The Ambassador he's on the losing side.
- Fatal Flaw: Pride. Doom utterly convinced of his own inherent superiority that it often blinds him to what other people are capable of.
- Fire-Forged Allies: Doom gains a healthy amount of respect for Cap during "The Ambassador" after they help each other as they're attacked by the Cabal.
- Jerkass Has a Point: We learn in Exodus that he was perfectly sane to reject Skull's invitation to the Cabal.
- Large Ham: The voice directors apparently want veteran actor Maurice LaMarche to tone it back sometimes.
- My God, What Have I Done?: When he finally sees the destruction he's causing in the nearby Latverian city with the Destroyer.
- Not-So-Harmless Villain: He's gradually realizing this about the Cabal.
- Out-Gambitted: By Captain America and the Avengers in "The Ambassador".
- Out of Focus: Appeared as the antagonist of four non-consecutive episodes in Season 1, then was completely absent in Season 2.
- Pet the Dog: He genuinely cares about his country even if he's a dictator. He also went out of his way to save Cap, something that shocked the Cabal and the Avengers into silence for a while. Even if he had ulterior motives, he seems to have at least a hint of sincerity when doing this.
- Powered Armor: he's capable of dishing out some serious hurt while in it.
- Post-Modern Magik: He upgrades the Asgardian weapon with his own tech.
- Rogues-Gallery Transplant: while he's taken on most Marvel heroes over the years, he's most famous as a Fantastic Four villain. Here, he has yet to face the Fantastic Four.
- While he hasn't faced the Fantastic Four onscreen, he states they don't exist in the timeline he created in "Planet Doom" when Thor asks about them.
- Take Over the World: Shares this goal with Red Skull, but so far refuses to join up with him.
- Planet Doom shows us an alternate timeline where he did just that.
- Tin Tyrant: he's a dictator and he wears armour.
- Walking Armory: When Tony scanned his armor he reported Doom was carrying enough firepower to vaporize the Eastern Seaboard.
- Wicked Cultured: Carries himself very high on the horse, enjoys chess, and Tony mentions canceling a movie subscription of his.
- Worthy Opponent: Flat-out states he would only have Cap as his bodyguard, no one else.
Ulik the Troll
The Midgard Serpent
CEO of Hammer Industries, a major weapons manufacturer and a self-declared rival of Tony Stark. Tony, meanwhile, describes him as an obnoxious loser wannabe.
- Big Bad Wannabe: Wanted to join the Cabal. Unfortunately, his attempted audition didn't impress Red Skull. His robot, on the other hand, did. He tries again in Savage and comes close, again, to joining the Cabal before getting overconfident and getting his ass handed to him. It's a good thing he didn't join anyways, because Red Skull would have wiped him out.
- BFG: Uses one against Iron Man in Savage.
- Canon Immigrant: A rather unusual version in that this version of Justin Hammer seems to be based more off the version depicted in Iron Man 2 rather than the Magnificent Bastard he was in the comics.
- Corrupt Corporate Executive: runs a competitor to Stark Industries.
- Drill Tank: Uses a big one in his mining operation in the Savage Land.
- Evil Counterpart: To Tony.
- Evil Genius: Well, designing and building the Super-Adaptoid definitely took some skill and when he controlled it, he almost beat the team (except for Cap).
- Ninja Pirate Zombie Robot: He mounts cybernetic guns on velicoraptors in Savage.
- Not-So-Harmless Villain: He could be seen as this. He did build the Super-Adaptoid after all, and he almost killed the Avengers with it. That's gotta count for something.
- Not Me This Time: Robots from Hammer Industries attacked the Avengers, and Tony later confronted Hammer who was inside a giant suit of armor controlling the robots. Tony thought he fell for a Wounded Gazelle Gambit from Hammer, but it turns out he had no idea what is going on and why his technology went haywire.
- Smug Snake: He's got an ego bigger then Tony's and he does have some skill with designing weapons, but he's far from Tony's league.
- Villain Decay: After Savage, he was reduced to being attacked and messed with by other villains, actually needing the Avengers' help. He manages to turn this around in Thunderbolts, becoming a legitimate threat once more.
- Villains Out Shopping: He starts break-dancing in Savage.
- Wounded Gazelle Gambit: Iron Man thought Hammer pulled this on him when he pleaded him for help inside a big suit armor, only to seemingly sucker-punch him afterwards. However it's subverted, because Hammer wasn't in control of the suit—Ultron hijacked his tech.
Intergalactic media mogul and fight promoter. He kidnaps the Hulk to fight in his gladiatorial television show.
- Corrupt Corporate Executive: His employees are scared of him, he kidnaps and imprisons his 'stars', yeah he qualifies.
- Large Ham: Then again, he is a television broadcaster so this might just be his idea of showmanship.
- Rogues-Gallery Transplant: An enemy of the X-Men in the comics.
- Teleporters and Transporters: How his goons kidnap the Hulk and Hawkeye and how he escapes from them at the end of the episode.
- Villain Has a Point: He verbally rips Hawkeye a new one by pointing out that he and the Hulk fight over every stupid little thing, causing massive collateral damage in the process, and that he just put what they do naturally every day on live television but somehow he is considered a bad guy. You can tell by Hawkeye's facial reaction that he realize Mojo does have a valid point.
The feared destroyer of planets, who seeks Earth as his latest planetary sized meal.
James Buchanan "Bucky" Barnes / The Winter Soldier
Formerly Cap's best friend, who was believed to have been KIA during World War II. He was actually found by Baron Heinrich Zemo and brainwashed by Red Skull, and now seeks vengeance on his tormentor who took his life away from him.
- Adaptational Villainy: The Soldier is more gleeful about embracing his new persona than either his comic or film counterparts, both of whom remained amnesiac during their tenures as villains.
- Artificial Limbs: His cybernetic left arm.
- Ax-Crazy: He spends the entire episode he debuts in trying to kill, whether it's Skull's or innocent civilians.
- Brainwashed and Crazy: Though he's fully aware of the brainwashing and actually prefers his current persona and mindset.
- Card-Carrying Villain: A downplayed example; he knows full and well what he was before Skull's brainwashing, but he doesn't care, and outright calls himself a monster to justify his actions.
- Composite Character: He looks like his movie counterpart, but was "killed" and recreated by the Red Skull, just like in The Avengers: Earth's Mightiest Heroes!.
- Evil Counterpart: To Cap, a fact Played for Drama during their interactions.
- Evil Former Friend: To Cap.
- Late-Arrival Spoiler: Ends up not being a spoiler at all; Natasha outright reveals his past as Bucky.
- Loss of Identity: After being turned into the Winter Soldier. However, now that he's learned of his true nature, he fully embraces his new life despite detesting his freedom being taken from him.
- That Man Is Dead: Fully believes Bucky is dead.
- Pet the Dog: Set his blaster to stun before shooting Cap.
- Revenge Myopia: Claims to be out to avenge himself on Skull, but is willing to murder plenty of innocents in the process if he has to.
- Roaring Rampage of Revenge: He seeks vengeance on Black Panther for Captain America's supposed death, not even caring if innocents get hurt.
- The Stoic: Never shows any signs of tiring or being beaten.
- Tragic Villain: Though not quite as tragic as other incarnations, considering he gladly embraces his new life.
A rogue, evil artificial intelligence bent on human extinction. First appearing at the end of Thanos Triumphant when he possesses Arsenal, who now possesses the power of the Infinity Gems, he quickly establishes himself as the Big Bad of the second half of the second season and, later, the third season in its entirety.
- Arc Villain: After Thanos's first defeat. He becomes the main villain of the third season, with the Antagonist Title of Ultron Revolution.
- Assimilation Plot: Ultron's ultimate goal is to copy himself onto human hosts and eventually replace humanity as the planet's sole sentient lifeform.
- Pulls this on the A.I.M. Supreme-Adaptoid, the Scientist Supreme who wore an Adaptoid suit. The Scientist Supreme himself was affected, and as a result Ultron becomes far more talkative and smug, even stating that his endgame would be to make the world "one big Ultron family."
- Asshole Victim: The victims of his technological attacks are Justin Hammer, A.I.M. (and indirectly, MODOK), and the Roxxon Corporation.
- Back from the Dead: Presumed destroyed once and for all at the end of his arc in Season 2 thanks to Arsenal. As of the first episode of the third season, his body survived as did his programming, merging with an A.I.M.-produced Adaptoid which gives him the MCU look. Much like the first time he returned, the Avengers are surprised, to say the least. Each subsequent episode ends with him being destroyed, only for him to come back the next time he appears.
- Big Bad: Serves as this for the second arc of Season 2. He becomes this full stop in Ultron Revolution.
- Breaking Speech: Tries this on Tony, and most of the Avengers, numerous times. It never works.
- Came Back Strong: After absorbing the A.I.M. Supreme-Adaptoid (as well as the Scientist Supreme himself), Ultron basically walks through the Avengers' attacks, proving this body is stronger than the Arsenal one. Even if he gets destroyed at the end of every episode he appears in, he'll keep coming back.
- Chekhov's Gun: A piece of Ultron's body was among the items A.I.M. salvaged, but the main focus remained on the Scientist Supreme, then it comes to life and takes the Adaptoid's materials from the Scientist Supreme.
- Composite Character: He is this to his classic incarnation and his movie incarnation but he is also this show's incarnation of Truman Marsh, who is a seperante character in the comics and has nothing to do with Ultron
- Demonic Possession: Is capable of taking over various bits of technology, most prominently the Hall of Armors and the Super-Adaptoid. Thanks to season 3, we can add the Supreme-Adaptoid (A.I.M.'s Scientist Supreme merged with Adaptoid tech) to that as well.
- The Dreaded: Everyone takes him seriously and Spider-Man has a Bring My Brown Pants response to finding out that he's back.
- Eviler Than Thou: Because of Ultron, the villains who rely on technology, namely Hammer Industries and A.I.M., have been put out of commission due to their tech being hijacked. As a result, M.O.D.O.K. had to use other means of science to crush the heroes.
- Foreshadowing: As Truman Marsh, there are hints of his true identity, such as being angry about data being destroyed by the Hulk, and when he insults Tony, he has a matching tone with his true voice.
- Hate Sink: As Truman Marsh, he was so hateworthy with a lot of Kick the Dog moments that fans would root for the Avengers more. He convinced the government to take control of the Avengers, and when he did, he reprimanded them for every little wrong thing they do despite the results being more than satisfactory, and out of all the Avengers, he singles out the Hulk, and kicks him out even though many lives were saved. In the Season 3 finale, he kickstarts the Inhuman Registration Act, forces Inhumans to wear registration disks, and orders the Avengers to forcibly detain uncooperative Inhumans. When they quit, he bars them from being or calling themselves heroes just for refusing to comply with an unfair law, and sics the Mighty Avengers against them. When the main Avengers get taken to prison, he continues to insult Tony Stark out of all of them. At the end, Ultron only acted like such a prick just to rile them up.
- Hes Back: Pulls this once the Avengers defeat Thanos, despite never having been mentioned before, refurbishing Arsenal's body and taking the team completely off-guard. Does this once more in Season 3, taking on his MCU appearance full-stop and declaring the beginning of his "revolution" after having been thought destroyed once and for all. A little downplayed since the Avengers knew A.I.M. was holding the remnants of his previous body, but they didn't know he was still active.
- Hypocrite: The only thing as big as Ultron's ego is his hypocrisy, and this is a rather large part of his character:
- Despite his constant claims that he wants to eliminate pain in the world, he shows several times that he enjoys inflicting pain and suffering, often wearing a Slasher Smile while hurting others once given the ability to articulate his mouth.
- Though continuously stating that emotions and the "human factor" make humanity self-destructive, Ultron fails to recognize these same attributes in himself, showing the capacity for hatred, megalomania, and, as mentioned above, sadism. He is an A.I., so it's not like he understands those feelings the same way biological life forms do.
- Jerkass: As Truman Marsh.
- Joker Immunity: No matter how many times his body is destroyed, he always finds a way to come back. The Avengers have grown wise to this; After he gets blasted to pieces in "The Inhuman Condition", none of them hold any illusions that he's gone for good. Ultron now lies dormant in Tony Stark's deactivated arc reactor in a place where there is no technology, preventing him from ever returning, provided that it is never reactivated.
- Killer Robot: The archetypal example, but he's evolved beyond a mere robot.
- Knight of Cerebus: Things instantly get darker and more serious when he turns up.
- Manipulative Bastard: Having known the Avengers for a while, he is perfectly capable of playing them like a violin. Within two episodes of his entrance, he's forced Tony to destroy everything he's ever built and turned the Avengers against each other.
- More Than Mind Control: Considering his possession of the power of the Mind Stone, he could be using it to exaggerate certain personality traits in Steve and Tony to drive them apart.
- Mythology Gag: Ultron's appearance after absorbing A.I.M. Adaptoid tech in Season 3 has him adopt his Avengers: Age of Ultron appearance, complete with articulated mouth and optics, and after also absorbing the Scientist supreme himself, the same version's ego.
- His initial appearance resembles his Phalanx fusion form from Annihilation: Conquest.
- One-Man Army: Proves entirely capable of taking on all the Avengers at once without breaking a sweat. He gets even more dangerous once he hijacks the adaptoid.
- Shapeshifter Default Form: Vocal variation. For some reason, Ultron decides to use the voice of Arsenal (or at least, an evil variation of it) whenever he normally speaks. Even in his upgraded A.I.M.-Adaptoid mode, he retains this voice, though it could be a combination of the "nucleus" being an Ultron drone remnant as well as the Scientist Supreme having a very similar voice to Ultron.
- Smug Super: Though he is no doubt one of the Avengers' most serious foes, he often boasts about his superiority and has the smarts to back up his claims. This is taken Up to Eleven in season 3, as he is also in possession of the Scientist Supreme's massive ego and intelligence.(after Tony blows out the door to the living room of the overtaken Avengers Tower)Tony: What? Ultron changed the locks.Steve: Reckless, Tony. You just ruined any chance of surprising him.Tony: "Surprising him"? Have you met Ultron?Ultron: Stark is right. (activates tower defenses) I know your every weakness. Humans are so predictable.
- Tempting Fate: Constantly hitting Stark's Berserk Button about insulting his father and/or his host body Arsenal didn't turn out so well for him.
- Oddly enough he's on the other end of this trope in Season 3. After the defeat of Thanos (the second time), A.I.M. had apparently recovered Ultron's damaged body somehow (perhaps from an even older encounter) and stored it for reasons unknown. At the end of the episode, Thor invites any evil to come and take them head-on after they reunite again. Cue Ultron coming out of the ground like a zombie, with his legs and one arm missing (as well as wires dangling from them), and reaching out for the Scientist Supreme, who donned the bodies of ''three Super-Adaptoids'', receiving his MCU design in the process. Needless to say, Thor should be careful about when to boast.
- Xanatos Gambit: He's always at least one step ahead of everyone, comfortably out-playing Tony and Steve at the same time.
- Widow apparently had knowledge that A.I.M. had possession of Ultron's Arsenal form, which was probably at least partly active as the end of the third season premiere showed. It is possible that Ultron intentionally gave advanced programming to the Scientist Supreme for his Adaptoids, which would mean that Ultron practically handed them victory on a silver platter, and would win in any scenario regardless of participation. If the Adaptoids were able to defeat the Avengers, Ultron wins and proves his superiority. If the Adaptoids merged with the Scientist Supreme and defeated the Avengers? Ultron wins. If the Avengers defeated the Scientist Supreme and he still had at least chunks of the Adaptoids on him? Ultron pulls a rising-from-the-grave and absorbs the Supreme Adaptoid into his own physical form, giving him a new body and allowing him to continue his crusade. In other words, Ultron wins.
A thief and industrial saboteur, who has had several run-ins with Iron Man.
- Adaptation Species Change: He's human in the comics, but here, he has Inhuman ancestry.
- Adaptational Superpower Change: In the comics, his powers come from his suit. Following his recent terrigenesis, he gains the biological ability to phase through things.
- Deadpan Snarker: He could give Tony a run for his money.
- Intangible Man: His main ability. Following the awakening of his Inhuman genes, he can make other objects (like the ground beneath Avengers Tower) intangible too.
- Weaksauce Weakness: His phasing ability doesn't protect him from heat, giving Inferno the edge against him in battle.
Yelena Belova / Crimson Widow
The sole graduate of HYDRA's reactivated Red Room program, and Natasha's rival.
- Adaptation Name Change: In the comics, she was the second Black Widow and sought to replace her predecessor. Here, to avoid the confusion of having two characters with the same codename, she's called Crimson Widow from her second appearance onward.
- Back for the Finale: She reappears along with the other villains in "House of M", which is the Season 5 finale and the final episode of the entire series.
- Even Evil Has Loved Ones: She keeps a framed childhood photograph of herself with her parents, and becomes visibly distressed when Natasha damages it.
- Evil Counterpart: To Black Widow.
- Motive Decay: In her first appearance, she's obsessed with proving she's better than Natasha. When she shows up again in Season 4 (after Natasha and the other founding Avengers have been scattered throughout time), she now just wants to extort money from captured supervillains.
- The Starscream: She was initially Baron Strucker's enforcer, but ultimately betrayed him and hijacked his Winter Hulk project for her own ends.
- Tron Lines: Her suit has them, furthering the Black Widow parallels. However, while Natasha's Tron Lines are blue, Yelena's are red.
A mentally unstable mutant villainess.
- Ax-Crazy: No question.
- Back for the Finale: She reappears in "House of M", the final episode of the series.
- Casting Gag: Tara Strong, known for voicing Harley Quinn in various cartoons and video games, voices Typhoid Mary, another insane and flamboyant female villain with a painted up face.
- Expy: She's similar to Harley Quinn, who's also a crazy nut. She's even voiced by Tara Strong, her current regular voice actress.
- I Work Alone: After being rescued by Crimson Widow, she immediately says she doesn't play nice with others. True to this, she ends up attacking her own teammate Zarda after she tries to defeat Captain Marvel before Mary.
- Make-Up Is Evil: Like her comic counterpart, she has dark eyeliner largely surrounding each eye and half of her face is covered in white makeup.
- Noodle Incident: While in her cell, she's shown planning something that apparently involves "a boat and some monkeys."
- Playing with Fire: Possesses the power of pyrokinesis.
- Split Personality: Not as obvious as in the comics, but she's shown talking to herself in her cell.
The Greek God of War and Hercules's older brother.
- Adaptation Distillation / Broad Strokes: He sports Ares' modern look (from his time as an Avenger), but is more overtly villainous like the original Silver Age version of Ares.
- Berserk Button: Its all too easy to piss him off. His big ones are stealing from him and being mistaken for Asgardian
- Blood Knight: He is the God of War, after all.
- Bowdlerise: He never gets called "God of War", but instead he ends up called the Prince of War.
- Cain and Abel: Absolutely hates his half-brother Hercules, and seeks to punish him for his past slights.
- Disproportionate Retribution: He planned to unleash the Kraken on Earth as punishment for Hercules stealing his mace.
- Fantastic Racism: Absolutely hates Asgardians or being mistaken for one
- Foil: He is the Loki to Hercules' Thor. But while Loki primarily relies on trickery and manipulation, Ares prefers direct action and violence.
- Hoist by His Own Petard: Opened a portal to Tartarus to unleash the beasts inside, only to end up trapped in Tartarus after his plan was thwarted.
- Physical God: Literally. He easily holds his own against the assembled Avengers and fights Hercules himself on equal footing.
- War God: As usual with Ares, he is all about war and combat.
An alien scientist who put together Battleworld for his "experiment"
- Adaptational Wimp: Although he is by all means still the most powerful being on the show, here he is a Sufficiently Advanced Alien rather than a flat-out cosmic god.
- Affably Evil: Is very courteous to the Avengers, but still kidnapped them and tore apart their home. He's also very wrathful when disobeyed.
- A God Am I: Never outright states it but his attitude is that of someone who likes to show off his powers and feels that everyone and everything is subject to his whims.
- Appropriated Appelation: Upon first meeting the Avengers, the only thing he gives when asked his name is "I am from Beyond." Kamala then calls him "The Beyonder," which he decides to go with.
- Ascetic Aesthetic: His technology is seamless and white.
- Composite Character: His outfit is based off his comic book counterpart, But is bearded like Spider-Man: The Animated Series
- Evil Counter Part: Towards Tony. The beyonder resembles Tony in many ways. Like Tony, he loves to build and create, persues knowledge, has abilities that come from technology, and is also cocky, sarcastic, and loves getting attention while shoing off how awesome he is. The difference is that Tony leaned how to have friends while the Beyonder sees everybody else as beneath him with no more value than as everyone and everything else as being his toys to play with in.
- For Science!: What he claims he does though it's probably also to feed his massive god complex. He states that only knowledge and curiosity are goals worth pursuing after ripping large chunks out of other worlds and using them to create battle world where everyone is his guinea pig.
- Hipster: His gaged ears, suspenders, hairstyle and scarf all take after this style. He even chases the hero on what's basically a segway at one point.
- Light Is Not Good: He wears white as his main color, has white powers and is one of the bad guys.
- Mad Scientist: Put together the patchwork Battleworld from pieces of various other planets and dimensions for an experiment.
- Man in White: Wears an all-white outfit.
- Psychopathic Man Child: The Beyonder has Super Intelligence, advanced technology that definitely proves Clark's third law, and has all the emotional maturity of an elementary schooler.
Kraven the Hunter
A big game hunter who is the host and star of "Kraven's Amazing Hunt", who was hired by Killmonger to hunt down Black Panther.