Sometimes, a brother can be the greatest person in a superhero's life. There are many teams of brothers who work very well together. Then, there are the brothers who are exactly the opposite. Marvel and DC Comics are full of brothers who hate their siblings and the world around them. They've battled their heroic brothers many times over the years, trying to kill their siblings and their friends every time they turn up.
Brotherly love can easily turn to hate. Some comic book brothers prove that, as they've all turned against their siblings in some way, shape, or form. Their rivalries with their brothers have created epic confrontations.
10 The Anti-Monitor Set Out To Destroy The Multiverse
The Anti-Monitor was the brother of the Monitor and the World-Forger. The master of antimatter, he eventually set out on a quest to destroy all positive matter in the Multiverse. He consumed universe after universe, gaining more power and making his home antimatter universe of Qward bigger. He would set himself in opposition to his brother.
The Monitor and Anti-Monitor would fight a Cold War for untold millennia. The Anti-Monitor always had the upper hand, his powerful assaults breaking through whatever the Monitor put in his way. Eventually, the Anti-Monitor would succeed in killing his brother but was ultimately defeated by the heroes of the DC Multiverse.
9 Ares Has Been A Terrible Half-Brother To Wonder Woman And Cassie Sandsmark
Ares is the God of War and the son of Zeus. He's been battling Wonder Woman since she came to Man's World before the two ever knew they were related. He's her most tenacious foe, with the two of them clashing multiple times over the years. He took a more brotherly relationship with Cassie Sandsmark, but it was all to manipulate her to take his side in the battle against Zeus.
Ares has repeatedly tried to defeat his half-sisters and embroil the world they protect in war. He's a fierce and powerful opponent, willing to attack them in unspeakable ways. Even when he is nice to them, it's just a ploy.
8 Jim Gordon Jr. Became A Serial Killer
Barbara Gordon was adopted by her uncle Jim at a young age, growing up with Jim Gordon Jr. as her brother. Jim was a deeply disturbed child, known for killing animals, and was implicated in the disappearance of one of Barbara's friends. Jim left Gotham but eventually returned and became a serial killer.
Upon Jim Gordon Jr.'s return, Barbara would warn her father that he wasn't to be trusted. She'd be proven right as he'd become a serial killer. He'd match wits with Dick Grayson, who was Batman at the time, and lose. Eventually, he'd end up helping Bruce Wayne against the Batman Who Laughs, but he was evil for most of his life.
7 Vulcan Tried To Kill Both Of His Brothers And The X-Men
Vulcan was the third Summers brother, ripped from his mother's womb by the Shi'Ar Emperor D'Ken after their parents were kidnapped by the aliens. A powerful Omega class mutant, Vulcan was raised as a slave and put in the Shi'Ar's hidden Earth compound. He would escape and end up under the tutelage of Moira MacTaggert and Xavier, sent on the second mission to Krakoa where his team was decimated by the island.
Thought dead, Vulcan would come back more powerful than ever and try to destroy the X-Men. He'd then go after the Shi'Ar for revenge, eventually taking over the empire. After losing an intergalactic war, Vulcan would eventually return to Earth and join the mutant nation of Krakoa.
6 Juggernaut Spent Years Trying To Kill Xavier
The Juggernaut is the strongest foe the X-Men faced. The step-brother of Charles Xavier, Cain Marko bullied his new sibling. He was jealous of Charles Xavier's intelligence and the Xavier fortune, and that jealousy got even worse when Marko gained the power of Cyttorak. Marko became the unstoppable Juggernaut and tried for years to kill his brother and his X-Men.
Whether it be on his own or with his best friend Black Tom Cassidy, Juggernaut was a deadly foe of Xavier and his team for years. Their old animosity has since dried up, but the years of hate make their current relationship a bit strained, even if it's mostly friendly.
5 Dog Logan Hunted His Brother Through Time And Space
Wolverine is the best at what he does, but he's not the best with family. The former James Howlett was raised beside his half-brother Dog, but neither knew it. They started as friends, but Dog grew jealous of James and the wealth of the Howlett family. Dog went along with his father when his dad decided to attack the estate. Dog was one of the few to survive when James's powers manifested.
Dog hunted James down later in life. He'd eventually corner him during his feral years but was pulled through time by diamonds imbued with temporal energy. Arriving in the present, he joined the new Hellfire Club and tried to destroy Wolverine and his X-Men.
4 Ma'alefa'ak Unleashed H'Ronmeer's Curse On Mars
Martian Manhunter is an extremely accomplished hero, but his life was defined by the destruction of his homeworld, Mars. The worst part of the tragedy was that it was his brother who unleashed the cataclysm that destroyed Mars. Ma'alefa'ak infected Mars with H'Ronmeer's Curse, eventually killing every Green Martian but his brother on the planet.
Ma'alefa'ak also survived the genocide of the Martians. He and his brother would battle many times over the years. Eventually, Martian Manhunter would triumph over his brother, destroying him in battle on the psychic plane. Luckily, Martian Manhunter avenged his people.
3 Loki Hated Thor For Millennia
There are few villains more important in the Marvel Universe than Loki. Originally a Frost Giant, Loki was taken in by Odin after the defeat of his people by Asgard. Raised alongside Thor, Loki had to deal with being in the God of Thunder's shadow. At first, they were friends, but Loki's jealousy would get the best of him. He grew to hate Thor over the years.
The two of them battled for millennia before Thor became a superhero on Earth. Loki's threat brought the Avengers together, and he'd soon battle against the heroes. Loki has worked on the side of angels, but his hatred of Thor always brings him back to the villainous side of things.
2 Kalibak Is His Father's Most Savage Enforcer
Jack Kirby's Fourth World saga is a generational conflict. Darkseid had two sons: Orion and Kalibak. Orion was traded to New Genesis for Izaya's son Mister Miracle and raised on the paradise planet. Miracle was thrown into the Armaghetto while Kalibak was at his father's side. He became the greatest enforcer of the forces of Apokolips, battling his two brothers many times.
Kalibak's physical power has made him strong enough to face off against Superman. Like the other highborn of Apokolips, he's always scheming for his father's throne. A savage warrior, Kalibak has tried to kill his brother Orion and adopted brother Mister Miracle many times.
1 Grim Reaper Has Been Tormenting His Brother In A Myriad Of Ways For Years
Eric Williams caused his brother Simon grief for years, committing crimes that Simon worked to cover up. Simon went to trial after taking an embezzlement rap for Eric but was bailed out by the Enchantress and experimented on by the Masters of Evil. This is when Simon became Wonder Man, and it led to Eric becoming Grim Reaper.
Simon died battling the Avengers and was resurrected, joining the team. As the Grim Reaper, Eric battled his brother and Earth's Mightiest Heroes many times. Wonder Man and Grim Reaper shared a proclivity for dying and coming back, their relentless hatred reigniting every time they see each other.