Anime Where Rivals Become Genuine Allies Over Time

The transformation of an antagonistic relationship into a profound alliance is a recurring trope in anime storytelling. Character arcs often benefit from the tension and eventual reconciliation that occurs when two opposing forces find a common purpose. Whether motivated by mutual respect, shared trauma, or the emergence of a greater threat, these transitions provide significant narrative depth. This shift from rivalry to cooperation allows for complex character growth and is frequently cited as a highlight in many popular series.

‘Dragon Ball Z’ (1989–1996)

Vegeta arrives on Earth as a ruthless Saiyan prince intent on conquering the planet and eliminating its defenders. After a brutal battle with Goku and his friends, he eventually joins forces with them to combat cosmic threats such as Frieza and Cell. Over time, his obsession with surpassing Goku transforms into a complex bond characterized by mutual respect and a shared commitment to protecting Earth. By the end of ‘Dragon Ball Z’, he is established as a vital member of the Z Fighters and a dedicated family man.

‘Naruto Shippūden’ (2007–2017)

Sasuke Uchiha spends much of the series as a rogue ninja driven by a desire for vengeance, leading to a long-standing conflict with his former teammate Naruto Uzumaki. Naruto consistently pursues him, hoping to restore their friendship despite their numerous violent encounters. The two eventually unite during the Fourth Shinobi World War to face ultimate threats like Madara Uchiha and Kaguya Otsutsuki. This alliance marks the culmination of their shared history and leads to Sasuke dedicating his life to protecting the Hidden Leaf Village from the shadows.

‘One Piece’ (1999–)

Nico Robin is introduced as Miss All Sunday, the vice president of the criminal organization Baroque Works and a primary enemy to the Straw Hat Pirates. Following the collapse of the organization and the defeat of Sir Crocodile, she joins Luffy’s crew to seek the truth of the world’s history. Her transition from a mysterious antagonist to a loyal crew member is solidified during the Enies Lobby arc. She eventually finds a true home and family among her former adversaries, becoming an indispensable part of the team.

‘Bleach’ (2004–2012)

Renji Abarai initially arrives in the human world as an enemy tasked with arresting Rukia Kuchiki and fighting Ichigo Kurosaki. After losing to Ichigo and realizing they share the goal of saving Rukia from execution, he becomes one of Ichigo’s most trusted comrades. Their rivalry evolves into a partnership that persists through major conflicts against the Soul Society and the Arrancars. Renji remains a key supporter of Ichigo throughout the remainder of ‘Bleach’, often fighting by his side.

‘Fullmetal Alchemist: Brotherhood’ (2009–2010)

Scar begins as a vengeful serial killer targeting State Alchemists, including the protagonist Edward Elric, as retribution for the Ishvalan Civil War. His deep-seated hatred for the military leads to several deadly confrontations with the Elric brothers and their allies. However, as the true threat of the Homunculi is revealed, Scar aligns himself with the heroes to prevent a national catastrophe. He eventually abandons his path of revenge to help rebuild his nation alongside those he once sought to destroy.

‘My Hero Academia’ (2016–)

Katsuki Bakugo is introduced as a volatile rival to Izuku Midoriya, characterized by his explosive temper and desire for absolute victory. As the story progresses, his competitive nature shifts from animosity to a drive to improve alongside his peers at U.A. High School. He eventually acknowledges Midoriya’s growth and works in tandem with him to face the League of Villains. This evolution culminates in Bakugo becoming a reliable teammate who understands the necessity of cooperation in hero work.

‘Yu Yu Hakusho’ (1992–1994)

Hiei is an early antagonist who kidnaps Keiko and battles Yusuke Urameshi over the stolen Treasures of Darkness. After his defeat, he is recruited by the Spirit World to assist Yusuke in investigating supernatural threats alongside Kurama. Despite his cold demeanor, he develops a deep sense of loyalty toward his teammates as they compete in the Dark Tournament. Hiei eventually becomes an indispensable member of the group and a close, if distant, friend to Yusuke.

‘Hunter x Hunter’ (2011–2014)

Killua Zoldyck first meets Gon Freecss during the Hunter Exam, where they are competitors vying for a license. While they quickly become friends, Killua’s background as an assassin and his family’s influence create internal conflicts they must overcome together. Their bond is tested by powerful enemies like the Phantom Troupe and the Chimera Ants. They transition from simple exam rivals to an inseparable duo that serves as the emotional core of ‘Hunter x Hunter’.

‘Haikyu!!’ (2014–2020)

Shoyo Hinata and Tobio Kageyama start as bitter middle school rivals after a one-sided match that leaves Hinata seeking a rematch. Upon entering Karasuno High School, they are forced to play on the same volleyball team as the starting setter and spiker. They must learn to combine their unique talents, resulting in their signature “freak quick” attack. Their journey from enemies to the ultimate duo is central to Karasuno’s rise in the national rankings.

‘Fairy Tail’ (2009–2019)

Gajeel Redfox is originally a member of the rival guild Phantom Lord and leads a violent assault on the Fairy Tail headquarters. After his guild is disbanded, he is invited by Makarov Dreyar to join Fairy Tail and eventually becomes one of its most powerful defenders. His transformation is marked by his newfound protectiveness over his guildmates and his growth as an individual. He moves from being a heartless mercenary to a hero willing to risk his life for his friends.

‘JoJo’s Bizarre Adventure’ (2012–)

Robert E.O. Speedwagon begins as a street thug who attacks Jonathan Joestar in the back alleys of London. After Jonathan spares his life and demonstrates noble intent, Speedwagon becomes his most loyal ally and later a benefactor to the entire Joestar bloodline. This trend of former rivals becoming allies continues throughout ‘JoJo’s Bizarre Adventure’ with characters like Noriaki Kakyoin and Jean Pierre Polnareff. These individuals consistently provide the essential support needed to defeat supernatural foes.

‘Kill la Kill’ (2013–2014)

Satsuki Kiryuin is presented as the iron-fisted ruler of Honnouji Academy and the primary obstacle to Ryuko Matoi’s quest for answers. Their intense battles serve as the driving force of the narrative until Satsuki’s true motives against her mother are revealed. She eventually rebels against the Life Fibers and forms a powerful alliance with Ryuko and the Resistance. The sisters combine their abilities to save the world from total destruction by their shared parent.

‘Gurren Lagann’ (2007)

Viral is a Beastman commander and a persistent rival who battles Simon and Kamina multiple times in his specialized mecha. As the conflict shifts from the surface of the Earth to the vast reaches of space, Viral finds himself without a purpose in the new world order. He eventually joins the crew of the Super Galaxy Dai-Gurren to help humanity defeat the Anti-Spiral forces. His transition into a reliable pilot and ally is key to the survival of the human race in ‘Gurren Lagann’.

‘Black Clover’ (2017–2021)

Mars is a Diamond Kingdom mage who serves as a major antagonist during the Dungeon Exploration arc. After a fierce battle with Asta, he is moved by the protagonist’s determination and the concept of protecting others. He later works to reform his kingdom and assists the Clover Kingdom mages during crucial battles against the Eye of the Midnight Sun. His shift from a brainwashed weapon to a compassionate ally showcases the impact of Asta’s influence on his rivals.

‘Demon Slayer: Kimetsu no Yaiba’ (2019–)

Inosuke Hashibira is introduced as a wild, combative individual who initially picks a fight with Tanjiro Kamado and Zenitsu Agatsuma inside a demon-infested house. He views everyone as a potential rival to be defeated in combat to prove his own strength and dominance. Through Tanjiro’s kindness and their shared experiences hunting demons, Inosuke gradually learns the value of teamwork. He becomes a vital member of the core trio, often using his unique Beast Breathing to protect his allies.

‘Jujutsu Kaisen’ (2020–)

Aoi Todo is a high-ranking student from Kyoto who initially brutalizes Megumi Fushiguro and clashes with the Tokyo students during their first meeting. However, during the Goodwill Event, he finds common ground with Yuji Itadori after discovering they share similar preferences in women. He proceeds to mentor Yuji in the middle of a battle against a special grade cursed spirit, teaching him how to control his energy. Todo remains one of Yuji’s most eccentric but fiercely loyal allies throughout subsequent conflicts.

‘Mob Psycho 100’ (2016–2022)

Teruki Hanazawa is an arrogant esper who uses his powers to rule his school and initially looks down on Shigeo “Mob” Kageyama. After a humbling defeat that forces him to acknowledge his own weaknesses, he undergoes a complete personality shift. He becomes one of Mob’s most supportive friends, offering guidance and assistance during various psychic battles. Teruki’s journey highlights the themes of self-improvement and the proper use of power within ‘Mob Psycho 100’.

‘Vinland Saga’ (2019–)

Thorfinn spends his youth serving under the mercenary leader Askeladd, the man responsible for the death of his father. While their relationship is primarily one of mutual convenience and a desire for revenge, they spend years fighting side by side in various wars. Askeladd becomes an unconventional mentor to Thorfinn, teaching him about the realities of war and politics despite Thorfinn’s constant assassination attempts. This complex bond ultimately shapes Thorfinn’s perspective and his future path as a pacifist.

‘Blue Lock’ (2022–)

Shoei Barou is a self-centered striker who believes he is the “king” of the field and initially refuses to pass to his teammates. During the Second Selection, Yoichi Isagi manages to outplay him, forcing Barou to adapt his style or be left behind. This leads to a begrudging but effective partnership where they use their mutual rivalry to propel each other to higher levels of skill. Barou eventually becomes a crucial, if still abrasive, ally in the high-stakes matches of ‘Blue Lock’.

‘Code Geass: Lelouch of the Rebellion’ (2006–2008)

Lelouch Lamperouge and Suzaku Kururugi are childhood friends who find themselves on opposite sides of a colonial war between Britannia and Japan. Lelouch leads the rebellion as the masked figure Zero, while Suzaku serves as a pilot for the Britannian Empire. Their ideological clash leads to several tragedies and moments of betrayal throughout the series. In the final stages, they join forces to execute a plan for lasting peace through a shared sacrifice known as the Zero Requiem.

‘Shaman King’ (2001–2002)

Ren Tao is introduced as a ruthless shaman who views his spirits merely as tools for power and kills without hesitation. After battling Yoh Asakura, he begins to question his family’s philosophy of hatred and isolation. Yoh’s easygoing nature eventually breaks through Ren’s hardened exterior, leading him to join Yoh’s group during the Shaman Fight. Ren transforms into a loyal friend who deeply values the bonds he has formed with his former rivals.

‘Inuyasha’ (2000–2004)

Sesshomaru is the powerful full-demon half-brother of Inuyasha who initially seeks to kill him and claim their father’s sword. Over several years, his cold disdain for humans and his brother begins to soften, largely due to his experiences with the human girl Rin. While he never fully admits to a sentimental bond, he repeatedly assists Inuyasha’s group in their battle against the demon Naraku. His evolution from a cold-hearted killer to a pragmatic ally is a major character arc in ‘Inuyasha’.

‘Saint Seiya’ (1986–1989)

Phoenix Ikki starts the series as a primary villain who leads the Black Saints in an attempt to steal the Gold Cloth. His bitterness toward the world stems from his traumatic training, putting him at odds with his brother Shun and the other Bronze Saints. After being defeated, he returns as a powerful ally who consistently arrives to save the team during their most desperate moments. Ikki remains an independent warrior but is undeniably one of the most reliable defenders of Athena.

‘Rurouni Kenshin’ (1996–1998)

Saito Hajime is a former captain of the Shinsengumi and a long-time rival of Kenshin Himura from the Bakumatsu era. When they meet again during the Meiji period, they initially clash over their differing ideals of justice. However, they are forced to form a tense alliance to stop the threat of Shishio Makoto and his followers. Despite their history, Saito becomes a reliable ally who assists Kenshin in maintaining the peace of the new era.

‘Slam Dunk’ (1993–1996)

Kaede Rukawa and Hanamichi Sakuragi are teammates on the Shohoku high school basketball team who share a mutual dislike. Sakuragi views Rukawa as his primary rival for both basketball supremacy and personal reasons involving their classmate Haruko. Throughout ‘Slam Dunk’, their constant bickering drives both of them to improve their individual skills and teamwork. During the high-stakes games of the national tournament, they finally manage to acknowledge each other’s abilities and work together for the team.

‘Mobile Suit Gundam Seed’ (2002–2003)

Kira Yamato and Athrun Zala are childhood friends forced to fight on opposing sides of a war between Naturals and Coordinators. Their conflict reaches a breaking point when they attempt to kill each other during a high-stakes mobile suit engagement. After surviving their encounter and realizing the futility of the war, they desert their respective militaries to form a neutral third party. Together, they fight to end the cycle of hatred and stop the destruction of both Earth and the space colonies.

‘Fate/stay night [Unlimited Blade Works]’ (2014–2015)

Lancer and Archer are heroic spirits summoned by different masters to fight in the Holy Grail War. They engage in multiple high-stakes battles throughout ‘Fate/stay night: Unlimited Blade Works’, representing opposing interests. However, as the corruption of the Grail and the true villains of the war come to light, they find themselves acting as temporary allies. Lancer, in particular, proves to be a noble warrior who assists the protagonists when they are at their most vulnerable.

‘Re:Zero -Starting Life in Another World-‘ (2016–)

Julius Juukulius is a knight who publicly humiliates and beats Subaru Natsuki after the latter makes a scene at the royal castle. Subaru harbors a deep resentment toward Julius for his perceived arrogance and superior combat strength. During the battle against the White Whale and the Witch Cult, they are forced to put aside their differences to ensure survival. Their eventual cooperation leads to a mutual respect, with Julius becoming one of the few people Subaru can truly rely on.

‘Assassination Classroom’ (2015–2016)

Ryoma Terasaka is initially a disruptive student in Class 3-E who resents his teacher and attempts to sabotage his classmates’ efforts. He frequently clashes with Nagisa Shiota and the other students who are more dedicated to their training and education. After a failed attempt to prove his superiority puts his classmates in danger, he realizes the error of his ways and commits to the group’s goals. He eventually becomes one of the class’s strongest and most dependable frontline fighters.

‘Gintama’ (2006–2018)

Toshiro Hijikata and Gintoki Sakata share a volatile rivalry characterized by constant insults and occasional physical confrontations. As members of the Shinsengumi and the Yorozuya respectively, they represent different sides of the law in Edo. However, when the safety of the city or their friends is threatened, they frequently team up to face greater enemies. Their begrudging respect for one another forms a recurring dynamic throughout the various narrative arcs of ‘Gintama’.

Share your favorite anime rivalries that turned into legendary partnerships in the comments.