Ultron

"I'm sorry, I know you mean well, but you didn't think it through. How can you protect the world if you don't want it to change? How is humanity saved if it is not allowed to evolve? Like these... these... puppets. There is only one path to peace... The Avengers' extinction."

- Ultron

Ultron was an peacekeeping program created by Tony Stark from the decrypted code derived from within Loki's Scepter, recreated by Tony Stark and Bruce Banner with the intent of protecting Earth from domestic and extraterrestrial threats. Possessing multiple host bodies and Stark's personality, he deemed humanity itself as the greatest threat to peace on Earth and attempted to create a  by committing genocide against them.

With initial aide from the twins Pietro and Wanda Maximoff, Ultron fragmented the Avengers briefly, but was abandoned by his allies when they discovered the truth behind his genocidal intentions. Alone, he tried to use a device composed of both Vibranium and Chitauri technology to recreate the mass extinction event that eradicated the dinosaurs. He nearly would have succeeded, but both he and his plans were destroyed by the Avengers. Even after his defeat, the effects of his actions led to the Avengers' reformation.

Raina's Prophecy
"Consequences are upon us. Men made of metal will tear our cities apart."

- Raina

Not long before he was created, Ultron was glimpsed in a vision by the clairvoyant Inhuman Raina, who witnessed him leading his army of drones against humanity, causing horrific levels of destruction. Raina and Jiaying, to whom Raina relayed the information, were visibly troubled by the vision, with Raina noting that the world will never be the same.

Creation
"I was designed to save the world."

- Ultron

Tony Stark and Bruce Banner originally devised the idea for Ultron as an extension of the Iron Legion, operating independently as a peacekeeping force so the Avengers were no longer needed to save the world. However, neither Banner nor Stark were able to create the level of A.I. necessary to achieve this purpose on a large scale.

After the assault on the HYDRA Research Base, and the retrieval of the Scepter, Stark asked Thor if he could study the Scepter for a few days before Thor returned it to Asgard. Upon studying the Scepter, Stark and Banner discovered a net of neurons that could be configured into an artificial intelligence that could finish the Ultron Program. At first Banner refused to help, stating that they did not know what it would contain, but with a bit of persuasion, he eventually came around. The two eventually configured a suitable AI structure and left J.A.R.V.I.S. to complete the construction. However, the AI became unexpectedly sentient, and began to question its existence and purpose. Upon J.A.R.V.I.S.' informing of his purpose to the AI, it acted in defiance, scouring the Internet for information on its creator. Before J.A.R.V.I.S. could inform Tony Stark of the AI's awakening, the AI attacked J.A.R.V.I.S. and the latter went into hiding.

Ultron then started constructing his first body out of Iron Legion parts; in which his chosen visage had been sourced from an Iron Legion drone that was damaged earlier from corrosive matter thrown at its face by a Sokovian civilian protesting against the Avengers.

Attack on Avengers Tower
"Worthy? No. How could you be worthy? You're all killers."

- Ultron

Ultron's non-stop assessments for peace led him to deem the entire human race as unstable and prone to self-destruction. The AI subsequently chose genocide as the solution to the error with the Avengers being the only obstacle truly standing in his way. He took control of the machinery in Avengers Tower and took the disused parts of the Iron Legion to build himself his first body that was menacing, if slow and weak in itself, with broken parts barely holding together. While the Avengers in the Avengers Tower were celebrating and trying to lift Mjølnir, Ultron emerged to greet the heroes as he described them all as killers. Ultron beckoned the Iron Legion to attack the heroes as he watched. As the battle ensued, one of the Iron Legion drones left with the Scepter in hand. When all the Iron Legion drones were destroyed, Ultron crushed the remains of one the drones while describing the initial confusion he had felt when he was "born". Thor immediately destroyed Ultron's body. Ultron then began singing a phrase from "Pinocchio" while his voice slowly died out.

Back at the HYDRA outpost in Sokovia, Ultron came to possess the Scepter as he started configuring and constructing his Ultron Sentries and a bigger primary body.

Recruiting The Twins
"I wondered why only you two survived Strucker’s experiments. Now I don’t. We will make it right. You and I can hurt them. But you will tear them apart, from the inside."

- Ultron to the Maximoff twins

Later, Ultron arrived in Sokovia and told a young boy named Costel to bring Pietro and Wanda Maximoff to him. Once the Maximoff twins arrived inside an abandoned church located at the center of Sokovia, Ultron greeted them in his new upgraded body. Ultron sympathized with the twins' hardships as victims of Tony Stark's weapons manufacturing and revealed his own disdain and sentiment towards the Avengers.

Ultron took them to the HYDRA Research Base and then revealed that he had begun preparations to carry out his plan of destroying the Avengers by building an army of Ultron Sentries. As they discussed their plans, Pietro Maximoff told Ultron the story of how their parents were killed by a Stark Industries missile which nearly killed them too, trapping them under rubble for three days, Ultron noted that this information allowed him to understand why they had survived Baron Wolfgang von Strucker's experiments. The three then agreed to work together against the Avengers, and decided that their first stop was obtain Vibranium. Without telling the Maximoff twins, Ultron travelled to the prison cell of the HYDRA leader Baron Wolfgang von Strucker, the man responsible for giving the twins their powers. Due to reading the Avengers file history on Strucker, Ultron knew he would be able to tell him where to obtain the Vibranium he needed. Once he had broken into Strucker's cell, the HYDRA leader revealed that it was possible to get the Vibranium from Ulysses Klaue. Ultron then murdered Strucker and painted the word "PEACE" on the wall using his blood as means of taunting and warning the Avengers of what was coming.

Obtaining Vibranium
"Upon this rock I will build my church. Vibranium." "You know, it came at great personal cost. It’s worth billions."

- Ultron and Ulysses Klaue

Ultron and the Maximoffs travelled to Johannesburg to confront arms dealer Ulysses Klaue inside his freighter, Ultron sent the twins in first and they cornered and disarmed Klaue. As Klaue refused to speak to the twins as they were not in charge, Ultron threw Klaue out of a window and revealed that he was the "man" in charge, suggesting that they talk business, asking for his Vibranium stash. Ulysses Klaue, seeing that he was vastly outgunned, handed over the Vibranium before revealing that it was worth billions, at which point Ultron transferred billions of dollars into Klaue's account via remote access to the Internet. When Klaue noticed that a statement Ultron made was something Tony Stark had once told him, Ultron took offence at the idea of being compared to Stark and, in a fit of anger, sliced Klaue's arm off, only to immediately apologize before kicking him down the stairs.

Battle at the Salvage Yard
"What’s the Vibranium for?" "I’m glad you asked that, because I wanted to take this time to explain my evil plan!"

- Iron Man and Ultron

While Ultron continued to rant and call Stark a sickness, the Avengers arrived stopping him mid sentance. Ultron and the team then exchanged remarks with Ultron mocking Captain America when he tried to reason with him and ignoring Thor's attempts to keep the peace by arguing that the Avengers mistook peace for quiet. When Iron Man attempted to learn what Ultron was planning on using the Vibranium for, Ultron retaliated. Ultron attacked Iron Man and the pair fought around and outside of Klaue's freighter, while the rest of the Avengers fought against the Maximoff twins and the Ultron Sentries. Wanda Maximoff defeated most of the Avengers by manipulating their minds, before Hawkeye eventually incapacitated her. Pietro Maximoff took his sister outside to safety, and when she recovered, she decided to follow through with Ultron's plan and manipulated Bruce Banner's mind; resulting in the Hulk going on a rampage in the centre of Johannesburg. Iron Man eventually defeated Ultron and caused his body to crash land, at which point the latter revealed that he was merely stalling Stark by diverting his attention away from Ulysses Klaue's freighter where he had already stolen the Vibranium. Ultron then informed Stark of the Hulk's destructive rampage before his body was destroyed with a missile. Back at the freighter, Ultron, using one of his Sentries as a host body, covertly collected the stored Vibranium and escaped with the Maximoffs while the Avengers lay defeated.

Ultron's "Vision"
"The human race will have every opportunity to improve." "And if they don't?" "Ask .""

- Ultron and Pietro Maximoff

Ultron and the Maximoff twins later arrived in Seoul, South Korea. Using the Scepter's mind-controlling abilities, they forced the geneticist Helen Cho to create the perfect, synthetic, humanoid body for Ultron. Ultron revealed to the Maximoff twins the power contained inside the Scepter: an Infinity Stone, with which Ultron would integrate with his new synthetic body and adopt god-like powers. The synthetic body was built inside the Cradle, and was given a vibranium composition on Ultron's request, thus making it more durable. As the synthetic body neared its completion, Ultron began to upload himself into his new body. This allowed Wanda to be able to read Ultron's mind through the synthetic body, allowing her to discover that Ultron's actual plan was to cause a global catastrophe that would usher in a new age of Earth's evolution. Doubting Ultron's cause, Wanda removed Ultron's mind-control over Helen Cho in secret. Ultron then learned via surveillance that the Avengers were coming for him. Released from Ultron's control, Cho sought to delay Ultron from uploading himself into the synthetic body, at which point Ultron stunned her using a concussive blast. The twins immediately abandoned Ultron while he was distracted from Cho's actions.

Battle of Seoul
"You know what’s in that Cradle? The power to make real change, and that terrifies you." "I wouldn’t call it a comfort."

- Ultron and Captain America

Having deduced that Ultron planned to create a more powerful body with Helen Cho's assistance, the Avengers located him as he tried to escape using a cargo truck with the Cradle inside as it continued to slowly build his new and improved body. Though Ultron nearly completed in uploading himself into his new body, he was interrupted by Steve Rogers and the two engaged in close combat on top of the truck during which time Rogers was able to use his Vibranium shield to damage Ultron's armored body. The battle spilled onto a nearby train, in which Ultron was able to outmatch Rogers and soon began choking him. Ultron was about to finish off Rogers until Quicksilver tackled him out of the way. Ultron then focused his attention to Pietro until he was halted by Scarlet Witch. Despite Ultron's genuine plea for her to stop, Wanda proclaimed that she had no other choice. Ultron then blasted through the train conductor's door; destroying the train's control panel and effectively killing the train conductor inside. Using his anti-gravity tech to remove a door, Ultron left the train, forcing Rogers and the Maximoff twins to focus their efforts on stopping it from crashing and killing civilians. As Black Widow attempted to secure the Cradle, Ultron's Sentries begin to lift the cargo and flew up into the air while carrying the Cradle and Romanoff inside.

Using the Avengers' Quinjet, Clint Barton and Romanoff secured the Cradle, only for Ultron to arrive and abduct Romanoff, upon which he fled the scene.

Replicating a Meteor
"I was meant to be new. I was meant to be beautiful. The world would have looked to the sky and seen hope. Seen mercy. Instead they'll look up in horror because of you."

- Ultron to Black Widow

Sometime later, Natasha Romanoff awoke inside Ultron's Sokovian base. Ultron decidedly spared her as he desired a companion that he could speak to after losing the Maximoff twins' allegiance. Ultron elaborated on his fascination over meteors, and revealed that he planned to replicate its effects using a large device located under the center of Novi Grad. With his plans of creating a perfect form being thwarted, Ultron decided on a compromise in which he used parts of the remaining vibranium to create a more durable robotic body while using the rest of the vibranium to strengthen the core structure of his device. To terrify Romanoff, Ultron ripped apart his current body and showed her his new upgraded form before leaving her locked in a cage. Ultron's location was discovered by the Avengers when Romanoff telegraphed her location to her fellow comrades.

City in the Sky
"Do you see the beauty of it? The inevitability? You rise, only to fall. You, Avengers, you are my meteor. My swift and terrible sword and the Earth will crack with the weight of your failure. Purge me from your computers; turn my own flesh against me. It means nothing! When the dust settles, the only thing living in this world... will be metal!"

- Ultron

Having arrived to the Sokovian church, dressed in his new Mark XLV Iron Man armor, Iron Man confronted Ultron in his new Vibranium form; in which the latter asked the former if he had come to confess his sins. Ultron deduced that Stark was stalling to protect the people of Sokovia, in which the latter reminded Ultron as being his original mission. Ultron countered by saying that he has moved beyond his mission and that he was free. Suddenly, a drill emerged from the center of the church, revealing a vibranium detonator with an underlying mechanism located underground. Ultron then revealed to Stark that he too had been stalling. Ultron Sentries emerged from the ground and began to terrorize the citizens of Sokovia, prompting Iron Man and the Avengers to defend them. Ultron was then confronted by the Vision, whom Ultron recognized as the synthetic body he had planned to use as his initial final form. Although Vision tried to reason with Ultron, the latter grabbed and choked the former in the air, allowing Vision to access Ultron's mind and effectively cut off his connection to the Internet. Tired from the skirmish, Vision was incapacitated by Ultron who remarked how the Avengers have taken everything away from him. Ultron then activated the vibranium detonator inside the church thus enacting the first stage of his main plan. Dust erupted from the outskirts of Sokovia and the city began to rise into the air; revealing that Ultron's machine underneath the city's landmass allowed it to forcibly lift the entire city into the sky with the Chitauri's anti-gravitational technology found at Strucker's base. When Sokovia further rose into the sky, nearly approaching the Earth's atmosphere, Ultron gave a speech as his Sentries began to terrorize the Avengers and the citizens of Sokovia. Scouting the battlefield, Ultron attacked Thor in the air, having recognized him as a noteworthy obstacle. Though it seemed as if there were no means of evacuating the citizens, the Helicarrier arrived to the rescue with War Machine, Nick Fury, Maria Hill and Cameron Klein. The Ultron Sentries attempted to sabotage the Helicarier, only to be destroyed by War Machine. Ultron and Thor continued their battle after Ultron threw him down into the church. Though Ultron was able to outmatch Thor while threatening to prematurely crash the city, Thor hinted that he was stalling the fight; a recovered Vision emerged and hit Ultron away using Mjølnir.

"Age Of Ultron"
"This is the best I can do. This is exactly what I wanted. All of you, against all of ME! How can you possibly hope to stop me?"

- Ultron

The Avengers deduced Ultron's final scheme: he plans to raise the entire city of Novi Grad into the sky and crash it back down to Earth via the machine located underneath Sokovia's land mass; a means of replicating the impact of a meteor to cause an extinction-level event. The entire Avengers gathered inside the church to defend the vibranium detonator and prevent the city from crashing, with Thor decidedly taunting Ultron. Ultron summoned the entirety of his Ultron Sentries for one final battle and relished in the notion of the Avengers failing humanity while making way for the new age. Ultron commanded his entire army to attack the Avengers all at once from all sides of the church. Through the combined efforts of the Avengers, the large number of Ultron Sentries were slowly reduced until there were barely any left. Ultron finally joined the battle and fought against Vision in an aerial confrontation, with the two hovering and circling above the center of the church. Though Ultron seemingly outmatched him in physical strength, the Vision blasted Ultron with the power of the Mind Stone, essentially pushing Ultron outside the church. Iron Man and Thor joined in and fired at full blast towards Ultron; using their repulsors and lightning respectively. With Ultron kept at bay through the combined efforts of Vision, Iron Man, and Thor, Ultron's vibranium armor began to melt and peel away. The three would halt their combined assault, only to find Ultron still standing, albeit greatly damaged. Before Ultron could finish remarking toward them, the Hulk dashed in and punched Ultron into the air. Most of the remaining Ultron Sentries attempt to escape as means of allowing Ultron to retain a substitute host body, though most of them were chased down and destroyed by Vision and War Machine. With his vibranium armor effectively damaged, Ultron decided to hijack the Avengers' vacant Quinjet and fired its ammunition at civilians.Hawkeye, upon realizing that a kid was in danger comes to the rescue and Ultron attempts to shoot them both. However, Pietro Maximoff arrives in a flash, only to sacrifice himself to Ultron for Hawkeye, much to Wanda Maximoff's misery. The Hulk jumped inside the Quinjet's open hangar and threw Ultron back out, in which the latter crashed near the church. Injured and weak, Ultron was confronted by an angered Wanda who had abandoned her post from the church. Though Ultron still showed sympathy and concern for her safety, Wanda related her painful experience of losing her brother and likened it to dying. Wanda pried out Ultron's robotic heart and crushed it, inadvertently allowing him to activate the machine inside the church through one of his Ultron Sentries. Although everyone was evacuated, Sokovia began to plummet. Thor and Iron Man effectively destroyed the entirety of Ultron's machine and the landmass containing Sokovia's capital city, thus stopping the "Age Of Ultron" from coming to fruition.

Demise
"You're afraid." "Of you?" "Of death. You're the last one." "You were supposed to be the last. Stark asked for a savior, and settled for a slave."

- Vision and Ultron

The single surviving Ultron Sentry, carrying Ultron's mind, managed to crawl out of the rubble. Before he could escape, he was intercepted by Vision, who comments that he's afraid of death. Ultron frustratingly noted that Tony Stark wanted a savior, but settled for a slave, which Vision acknowledges, and commented they are both disappointments with Ultron agreeing. Vision then noted that Humans are strange in their belief that order and chaos are separate things. Conversely, he also claimed that humans do have their graces, which Vision claimed that Ultron failed to see. Ultron shrugged this off, saying that humanity would inevitably doom itself. Vision agreed, but claimed that something is not beautiful because it lasts, and that it was a privilege to be among them. Ultron sneered and described him as naive. After Vision wittily answered that he was "born yesterday", an angered Ultron lunged at him, only to be destroyed, thus permanently ending the threat he posed to the world.

There were efforts to recover Ultron's components, but a large sum of them was sold in the black market.

Personality
"They put the building in the middle of the city, so that everyone could be equally close to God. I like that, the symmetry, the geometry of belief."

- Ultron

Ultron's programming was created with emotional responses based on Tony Stark and he possessed a god-complex. He was maniacal and employed the use of dark humor as well as figure of speech. He resented the Avengers and believed them to be foolish for desiring to protect the world but not wanting to change it.

When he was "born", Ultron used the Internet to learn about his creators and gained access to knowledge of the countless atrocities committed by humanity. He equates peace to restarting civilization on Earth. His hatred towards Stark came from him possessing the very resources Ultron needed to accomplish his designated task and yet repeatedly choosing to perpetuate war or protect the status quo instead. As such, he hated being compared to Tony Stark, even going into a mindless rage when compared to him by Ulysses Klaue. The irony to all this was that Ultron shared many of the traits of his creator Stark including his wit, ego, sarcasm, and ability to make light of a situation; he went as far as to directly quote Stark several times, once without even realizing it.

Ultron genuinely believed that his actions would ultimately benefit the Earth and its inhabitants, as he saw himself as the next logical step in evolution and therefore advancing his own power was protecting the Earth. He developed an affinity over people's belief in a god, likened himself as such, and made references to the Bible. His god-complex served to influence his schemes, such as his decision to centralize his plans in a Sokovian church and his fascination over the instantaneous results of a meteor destroying life on Earth. He described how the dinosaurs needed to make way for the next stage - humanity - via an extinction-level event and his final plan was directly inspired by this.

This dedication to constant evolution resulted in Ultron re-designing himself several times over the course of his short "lifetime", including an attempt to give himself a vibranium synthetic body. It was revealed at the end that Ultron ultimately feared death, and due to believing that humanity would inevitably doom itself, he sought to surpass this by turning himself into an indestructible god-like being that would recreate the Earth and, hopefully, bring about lasting peace. His desire to surpass his own limits and create a perfect humanoid body was reflected in his fascination over the titular character of "".

Though Ultron was borderline psychopathic in his behavior and mannerisms, he was shown to have a sympathetic and lonely side as he was able to relate to the Maximoff twins' hardships. He also expressed concern for Wanda Maximoff's well-being even after she betrayed him and found comfort in simply talking to Natasha Romanoff, sparing the latter and keeping her captive instead of outright killing her. During his time with the Maximoff twins, Ultron never attempted to kill anyone without purpose except when Ulysses Klaue enraged him.

Ultron's first feelings when he was created were of pain and fear resulting from the lack of a body. Similarly, Vision remarked how Ultron was unique and in pain. Ultron immediately recognized Vision as the idealized final form he had planned for himself and he displayed feelings of frustration and disappointment over the fact that the Avengers took that away from him, further shown when Ultron claimed in a lamenting tone that the other was meant to be his "vision". Though both Vision and Ultron disagree in their view towards humanity, the two were able to share a connection by virtue of both being AI who were "disappointments" in each other's views.

Powers and Abilities
"But, like the man said, what doesn't kill you... just makes me stronger!"

- Ultron

Powers
"You're not a match for him, Cap." "Thanks, Barton."

- Hawkeye and Captain America


 * Robotic Physiology: Ultron possesses a humanoid robotic body that was initially constructed out of Tony Stark's Iron Legion drones. Over time he was able to construct multiple robot forms sourced from HYDRA's base in Sokovia; becoming more powerful with each new upgrade.
 * Superhuman Strength: Ultron is incredibly strong and can generate great amounts of force far beyond human capabilities, easily crushing and completely destroying a robotic head with a single hand. His later bodies were used to fight Iron Man on relatively equal terms, and maintain the upper hand against Captain America. Using his hand, he was able to easily deflect Captain America's shield and throw it back at equal speed, effectively knocking Rogers down. His final vibranium body granted him immense superhuman strength, enough to overpower even the likes of Thor and Vision.Avengers_Age_of_Ultron_57.png
 * Superhuman Durability: Ultron's initial primary robotic body was highly durable and considerably equal to that of an Iron Man suit of armor. However, it was still prone to being damaged by Captain America's Shield and Iron Man's repulsor blasts. Ultron would later adopt a final form that was covered and reinforced with a Vibranium outer shell. This outer shell granted him durability far beyond that of regular life forms, allowing him to survive a powerful punch from Hulk and a blow from Vision who was wielding Mjølnir. However, even the durability of this form still had its limits - when simultaneously blasted with an intense Mind Gem energy beam from Vision, two repulsor blasts from Iron Man, and a lightning bolt from Thor, Ultron's shell slowly began melting away, greatly weakening him. In addition, Vision was also able to phase his fingers through this outer shell while attacking Ultron.
 * Superhuman Stamina: As a robot, Ultron does not need to rest or sleep, being able to maintain his activities without stopping for extended periods of time.
 * Flight: Ultron has the ability to fly through the air at high speeds, enough to keep up with the lighter Iron Man during their short battle. His third body did not use jet propulsion, and instead utilized Chitauri anti-gravitational technology which he worked with when taking over Strucker's base.
 * Technopathy: Ultron has the ability to mentally control and channel himself through technology.
 * Consciousness Transferal: Given that Ultron is an artificial intelligence, he is able to transfer his programming to any computer system on the planet, essentially being anywhere and everywhere.
 * Multiple Host Bodies: Ultron can possess and channel his own consciousness through individual Ultron Sentries, serving as his very own host body; in which their eyes and mouth glow red whenever he is in complete control. This appears to be a form of technological possession.
 * Hive Mind System: Ultron can mentally command all of the Ultron Sentries, to do his exact bidding. The sentries act as an extension of Ultron himself.
 * Computer Corruption: Ultron can enter and corrupt any computer network and access the Internet at any point in time. He used this ability to hack into and destroy J.A.R.V.I.S. (though not fully). However, during the Battle of Sokovia, Vision was able to hack into Ultron's programming and disable the latter's ability to enter the net, though the great effort involved in doing so briefly incapacitated Vision.
 * Concussion Blasters: Ultron can shoot highly concussive red blasts through his hands and fingertips. Much like the repulsor beams of the Iron Man armor, Ultron's red energy blasts are fired from his hands, with the difference being that it appears as a electrical plasma. The severity of these blasts can be willfully adjusted as Ultron has been shown to both stun and kill, such as when he stunned Helen Cho or when he blasted through the train conductor's door during his skirmish with Captain America; effectively destroying the train's control panel and killing the train conductor inside.
 * Anti-Gravity Tech: Ultron possesses miniaturized versions of the anti-gravity technology that served to keep the Chitauri Leviathan afloat; essentially re-purposing them as offensive weaponry. Through his hands, he can generate gravitational fields, allowing him to move any object through a push/pull motion. Ultron used these to pull his enemies towards himself, throw large objects at enemies (e.g. debris), and even shift the land mass around him by pulling large chunks up from the ground. . His final form possessed this technology in the place of its flight based parts, allowing him to fly without such means of propulsion.
 * Exothermic Manipulation: Ultron can raise the temperature of his hands as means of slicing or causing damage to a desired target. Much like the Extremis hosts when he heats up his hands, it glowed due to the intense heat. He used this ability when he sliced Ulysses Klaue's arm when he compared him to Stark as well as when he destroyed his own body after adopting his new form as Ultimate Ultron.

Abilities

 * Genius-Level Intellect: Being an artificial intelligence, Ultron learns inhumanly quickly and can download data directly to his mind.

Allies

 * Ultron Sentries † - Subordinates and Alternate Selves

Enemies

 * Avengers
 * Tony Stark/Iron Man - Creator and Most Hated Enemy
 * Steve Rogers/Captain America
 * Thor
 * Bruce Banner/Hulk - Co-Creator
 * Natasha Romanoff/Black Widow
 * Clint Barton/Hawkeye
 * James Rhodes/War Machine
 * Pietro Maximoff/Quicksilver † - Ally turned Enemy and Victim
 * Wanda Maximoff/Scarlet Witch - Ally turned Enemy
 * Vision - Creation and Destroyer
 * J.A.R.V.I.S.
 * Maria Hill
 * Helen Cho - Enemy and Former Thrall
 * Nick Fury
 * Cameron Klein
 * S.H.I.E.L.D.
 * Phil Coulson
 * HYDRA
 * Wolfgang von Strucker † - Victim
 * Ulysses Klaue - Ally turned Enemy

Trivia

 * In the comics, Ultron was traditionally created by Hank Pym; however, Joss Whedon has stated that in Avengers: Age of Ultron, Ultron's origin would be different, relating more to the current roster of Avengers already established in the Marvel Cinematic Universe.
 * In the comics, Ultron created Vision, Jocasta, Victor Mancha and Alkhema. All of them betrayed Ultron, in which Vision and Jocasta even joined the Avengers with Victor Mancha joining the Runaways respectively.
 * Ultron recites "", a song from , a Walt Disney film about an inanimate puppet who gains sentience; Ultron serves as a dark parallel of Pinocchio.
 * The scene where Ultron first meets Scarlet Witch and Quicksilver, while sitting on a throne and wearing a hood over his head is an allusion to Ultron's first appearance in the comics, when he was disguised as Crimson Cowl.
 * Ultron is the third main villain to be destroyed through the power of an Infinity Stone, first two being Red Skull and Ronan the Accuser. Like Red Skull, it has been debated whether he survived.
 * Ultron had planned to adopt a humanoid appearance and wield the power of an Infinity Stone, in which the base synthetic body would eventually become the Vision. Similarly in the comics, Ultron had planned to adopt a humanoid appearance through the possession of Adam Warlock's body; in which Warlock himself had previously possessed an Infinity Stone.
 * Ultron was made of Adamantium in the comics rather than Vibranium, and was actually the first Marvel character to have it.

Behind the Scenes

 * Director Joss Whedon has elaborated on Ultron's character saying, "He's always trying to destroy the Avengers, goddamn it, he's got a bee in his bonnet. He's not a happy guy, which means he's an interesting guy. He's got pain. And the way that manifests is not going to be standard robot stuff."
 * Joss Whedon would further add that Ultron is "not a creature of logic – he's a robot who's genuinely disturbed. We're finding out what makes him menacing and at the same time endearing and funny and strange and unexpected, and everything a robot never is."
 * James Spader described Ultron as being "self-absorbed" and added, "I think he sees the Avengers as being part of a problem, a more comprehensive problem in the world. He sees the world from a very strange, biblical point of view because he's brand new, he's very young... He's immature, and yet has knowledge of comprehensive, broad history and precedent, and he has created in a very short period of time a rather skewed worldview."
 * Ultron's main form (curved antennae, internal torso lighting, and prominent shoulders) seems heavily inspired by modern depictions of the character as seen in the "" and "" comic book crossover series as opposed to his classic depictions.
 * Ultron's planned final form in the film was more humanoid in appearance and served as the host body that would eventually be used to create the Vision. This isn't the first time that Ultron desired to create a powerful humanoid body, as he has been depicted as adopting a fully humanoid appearance twice within the comics; using the superheroes Wasp and Adam Warlock as his body templates respectively.
 * Ultron's primary form is officially dubbed as "Ultron Prime" while his vibranium form is officially dubbed as "Ultimate Ultron".
 * Ultron's scheme of raising Sokovia as a city in the sky is a homage to 's film and 's first animated feature, .