When the Avengers emerged as the world's premier superhero team, Baron Helmut Zemo recognized them as the greatest obstacle to Hydra's future.
To counter them, he assembled and financed his own superhuman strike force, the Masters, carefully selecting villains who mirrored the Avengers' greatest strengths.
His initial idea was to find twisted reflections of each Avenger, individuals capable of countering them through equally powerful abilities. The beast that now inhabited Emil Blonsky's mind and body was far easier to tame than the Hulk, although keeping him fed could become expensive. The brilliant Egghead had been horribly disfigured by his involvement with the Pym Particles that caused the Vernon Van Dyne Laboratories incident, an event that only fueled his obsession with understanding the technology. Chen Lu had once been a rival of S.H.I.E.L.D. before becoming infected by a powerful form of energy similar to the one that created Major Marvel. Cassandra Gillespie had experienced both romance and hatred toward Tony Stark, just like so many other women who crossed his path, but above all she possessed remarkable business instincts and sought to finance the services of her Mandroids.
Melissa Gold was an unexpected treasure. She had been subjected to Roxxon's experiments while they attempted to recreate the process that created Spectrum, only to be discarded when she failed to produce the desired results. What Dario Agger saw as scrap, Zemo saw as an unpolished gem. Amora was the easiest to recruit. She had arrived on Earth searching for Loki after being exiled from Asgard, accompanied by her loyal servant Skurge. It only took a few careful manipulations to convince her that her beloved Thor had murdered his brother, explaining why he had never returned to Asgard.
With such overwhelming power at his side, surely the Avengers would be no match.
Zemo's super-team was defeated with surprising ease, time and time again. The Avengers seemed to possess something far greater than power alone, perhaps a bond of friendship impossible to replicate, or simply flawless teamwork. Soon, pressure began mounting from Ophelia Sarkissian and Brock Rumlow, two of Hydra's highest-ranking figures who had spent years conspiring to replace Zemo as the organization's leader. He refused to allow that to happen.
The young actor Simon Williams was brought to Zemo's mansion in Leipzig. Simon struggled to control his newly acquired powers, and Zemo offered him treatment by draining his ionic energy through a machine built by Thinkerer and his apprentice Fixer. Secretly, Zemo used the absorbed energy to empower a new generation of devastating high-yield weaponry.
Zemo also forced Elihas Starr to involve one of his own mercenaries in another experiment, making him the test subject for the "Particular Doses," repeated injections of Pym Particles capable of increasing both size and strength. The chosen subject was Erik Josten. Zemo's plan was simple: unleash the naked giant in the middle of Times Square and blame the Avengers, claiming they had irresponsibly attacked a Hydra convoy transporting Pym Particles and caused Erik's contamination.
To strengthen his legal battle against the Avengers, Zemo hired attorney Janice Lincoln. At first, the trial seemed overwhelmingly favorable to the Masters, until the Avengers' lawyer, Jennifer Walters, discovered that the presiding judge had been threatened by the masked criminal known as The Beetle. The revelation forced the entire case to be thrown out and a new trial to begin from scratch.
Meanwhile, Enchantress sensed an immense mystical potential within Transia, a power she had witnessed once before. Zemo paid the Werbert Wyndham Mental Hospital to obtain legal custody of a young orphan living there and brought her to Leipzig. Her name was Wanda Maximoff, and her abilities were not only immensely destructive but completely uncontrollable. To better understand and manipulate her powers, Zemo called upon his close friend, psychiatrist Karla Sofen, assigning her to study Wanda through regular therapy sessions.
At the same time, Baron von Strucker, Hydra's second-in-command, repeatedly attempted to contact Zemo. One of his highest-ranking operatives, the supremacist Grim Reaper, claimed to have found his long-lost brother inside Zemo's castle. Strucker gradually abandoned his Hydra responsibilities in pursuit of the truth, infuriating the rest of the organization.
Zemo, however, saw greater potential than ever in Simon Williams. Now that the young man had won Wanda's heart, the teenage couple might become the very key to destroying the Avengers. The Masters' greatest operation was finally approaching.
An entire army of criminals now stood alongside Zemo. His Masters had grown into a massive and dangerous organization, filled with confused young recruits searching for purpose and opportunistic crooks seeking wealth, both things Zemo could readily provide if they helped him invade Avengers Mansion and destroy Earth's Mightiest Heroes once and for all.
After setting vehicles ablaze around the mansion's main gates and severing every line of communication with the outside world, the Masters surrounded the Avengers' headquarters, transforming it into the battlefield for a bloody war. Supervillains poured into the estate from every direction while Zemo, escorted by Wanda and Simon, marched toward the mansion's grand hall, where Captain America awaited him. The battle spread throughout the mansion as the Avengers desperately fought to contain their enemies without destroying the historic estate donated by the State of New York as their headquarters. When Major Marvel charged directly toward Zemo, he ordered Simon to stop her, forcing the young hero to assume his ionic form and hold her outside the grand hall, even though Zemo knew Simon might die if Major Marvel absorbed all of his energy while he remained in that state.
At last, Zemo faced his archenemy, Captain America, determined to rewrite the history books that had portrayed his grandfather as the loser for generations. With Wanda standing beside him, victory finally seemed within reach. Evil triumphed as Zemo knocked Captain America unconscious with the sheath of his sword. Standing over his greatest enemy, he raised the blade, prepared to drive the symbol of his victory straight through the patriot's chest.
Before he could strike, a devastating blast of corrupted magic pierced through the back of his neck and erupted from the tip of his nose.
Wanda's spell settled upon him as a chaotic curse, grotesquely reshaping every opening on his face, his eyes, mouth, ears, and nose, twisting them together into something resembling a piece of contemporary art. Unable to comprehend the betrayal or even utter a single word, Zemo watched the young witch collapse into tears while Captain America regained consciousness and rushed to protect her. Only then did he understand. The entire time, he had been deceived by the teenage girl he believed he had under his control. Wanda had achieved what she truly wanted: to be in the right side of history.
The America Thunderbolts was established by the United States government under the supervision of Mayor Wilson Fisk as a national initiative designed to transform imprisoned supervillains into state-sponsored heroes. In exchange for reduced sentences, the recruits were assigned official identities, designated territories to protect, and the responsibility of enforcing the Registration Act across the country.
The Thunderbolts America were assembled by the United States government as the public face of a controversial rehabilitation initiative, transforming some of the nation's most dangerous supervillains into state-sponsored heroes. Under the leadership of Citizen V, the team quickly became the government's premier response unit for superhuman crises, each member serving as the official protector of a different state while secretly struggling with the burden of their criminal pasts.
The Thunderbolts America's first public operation began with the emergence of a single government-sponsored hero. Following the implementation of the Registration Act, the vigilante Americop openly declared war against the federal government, attacking registration facilities and denouncing the law as an assault on the freedoms superheroes had fought to protect. In response, Wilson Fisk unveiled Citizen V as the first active member of a new generation of state-sanctioned heroes. Their confrontation quickly escalated into a brutal battle broadcast across the nation, ending with Citizen V defeating and capturing the rogue vigilante after a relentless duel. The victory marked the first successful enforcement of the Registration Act by a registered superhuman and instantly transformed Citizen V into a national symbol. In the days that followed, the government officially introduced the remaining members of the Thunderbolts America—Mach-X, Plantman, Charcoal, Songbird, Techno, Atlas, Meteorite, and Sentry—revealing that Citizen V's triumph had been only the beginning of a far greater initiative to redefine America's superheroes.
During a humanitarian mission in the Arctic, the team encountered the enigmatic hero Polestar after a mysterious electromagnetic anomaly disabled military satellites and communication systems across northern Canada. While Techno and Mach-X attempted to restore the collapsing infrastructure, Songbird and Atlas discovered that Polestar had been holding back an extraterrestrial energy storm capable of devastating the entire continent. Rather than arresting him for operating outside the Registration Act, the Thunderbolts reluctantly aided him in containing the phenomenon before allowing him to disappear without revealing his identity.
The team's public image suffered when Brother Nature exposed evidence that several corporations financing the Thunderbolts Initiative were secretly polluting protected forests across Vermont. Plantman refused orders to eliminate the activist and instead sided with him to restore the devastated ecosystem. Although the government successfully suppressed the scandal, the incident revealed that not every member of the Thunderbolts was willing to place political interests above innocent lives.
When the deranged genius Mad Man launched a series of biological experiments across abandoned industrial districts, Techno found himself engaged in a battle of intellect against a scientist whose inventions rivaled his own. Assisted by Mach-X's speed and Meteorite's overwhelming power, the Thunderbolts dismantled Mad Man's laboratory before his mutagenic virus could spread through several major cities, though Techno privately admitted that some of Mad Man's discoveries fascinated him.
The appearance of Hurricane forced the Thunderbolts into one of their most destructive operations to date. As violent storms ravaged the Gulf Coast, Atlas and Charcoal struggled to evacuate civilians while Songbird used her hard-light constructs to shield entire neighborhoods from tornadoes. After a prolonged battle through the eye of the storm, Meteorite managed to disrupt Hurricane's control over the atmosphere, ending a catastrophe that threatened multiple states.
Perhaps their greatest internal crisis occurred when Machinesmith infiltrated the federal defense network. Able to possess satellites, drones, military databases, and civilian infrastructure simultaneously, the cybernetic terrorist nearly seized complete control of the country's technological systems. Techno ultimately confronted his technological counterpart within a virtual battlefield, defeating Machinesmith by sacrificing portions of his own cybernetic systems to permanently isolate the villain from every connected network in North America.
The Thunderbolts later confronted Graviton after the former physicist attempted to elevate an entire American city into the upper atmosphere to create what he believed would become humanity's first "perfect civilization." Atlas pushed his body beyond safe limits by consuming repeated Particular Doses while Charcoal restrained collapsing structures long enough for civilians to escape. Together, the team prevented the city's destruction, though Atlas' heart nearly failed from the strain of maintaining his colossal form.
Their pursuit of Man-Killer became one of the program's most politically sensitive missions. Viewing the Thunderbolts as nothing more than criminals wearing patriotic uniforms, she systematically targeted corrupt officials responsible for creating the initiative. Citizen V eventually cornered her after a lengthy investigation, but her accusations regarding the government's manipulation of former villains planted doubts within several members of the team, particularly Atlas and Plantman.
The team's greatest test arrived with the emergence of Molecule Man, whose unstable mastery over matter threatened to erase entire regions of reality itself. Conventional military force proved completely ineffective, forcing every Thunderbolt to contribute. Techno devised the containment system, Songbird reinforced it using solid-light constructs, Atlas and Charcoal held the collapsing dimensional breach together through sheer physical strength, while Meteorite and Citizen V distracted the cosmic entity long enough for Sentry to intervene. Drawing upon the unimaginable power that had once made him Earth's greatest hero, Sentry contained the reality fracture, though the effort brought him dangerously close to unleashing the Void once again. The battle became the defining victory of the Thunderbolts America, proving to the public that even the world's most notorious former villains could stand between humanity and extinction—whether for redemption, duty, or reasons known only to themselves.