12 Superheroes Whose Best Friend Turned Into Their Archnemesis

Though they didn’t meet until college, Peter Parker and Harry Osborn quickly became the best of friends. Their relationship was eventually complicated by the fact that Harry’s father was the Green Goblin, archnemesis of Peter’s alter ego, Spider-Man. But what really complicated it was Harry proceeding to become the Green Goblin himself on two separate occasions, then croak, then come back to life as an even deadlier supervillain.

Falsely believing Spider-Man had slain his father, Harry snapped when he learned his BFF had been the wall-crawler all along. He put on his father’s costume, hopped on his glider, and targeted Peter’s apartment. Without any of Norman Osborn’s trademark goblin-strength, however, Harry was easily bested by Spidey - beaten into amnesia, in fact.

When those memories inevitably resurfaced, Harry took the time to re-create his father’s Goblin Formula and became the Green Goblin for real. His plotting and scheming eventually saw Peter and Mary Jane Watson trapped in a building that was about to explode, but Harry had second thoughts and gave his life to save them, sacrificing himself while calling Peter his “best friend.”

Years later, Peter and Mary Jane sold their marriage to Mephisto, and one of the many side effects was Harry coming back to life. Harry remained a staunch friend and ally of Peter thereafter - and a vocal opponent of his dad - until he revealed himself as Kindred, a new supervillain and the source of more than 50 issues of misery for Spider-Man.

After surviving the Holocaust, Max Eisenhardt changed his name to Erik “Magnus” Lehnsherr and began traveling the world. In time, he settled in Israel, where he volunteered his time at a psychiatric hospital for fellow victims of the Shoah. And that’s where he met Charles Xavier. 

Strangely enough, both men frequently debated the politics of mutants, and if they could ever peacefully coexist with humans, without ever telling one another of their mutant powers. A strike by Hydra forced them to reveal their abilities, but Magnus's ruthless response also convinced Charles that their views were irreconcilable.

The two parted ways, with Xavier going on to found the X-Men and Magnus taking on the name Magneto and forming the Brotherhood of Evil Mutants. Since then, the two have frequently gone head-to-head - Professor X once wiped Magneto’s mind clean - but they’ve also put their differences aside on numerous occasions, most recently in the founding of the mutant nation Krakoa.

Upon being recruited into the Green Lantern Corps, Hal Jordan was given the honor of partnering with the greatest Green Lantern of all time, Thaal Sinestro. The surly Sinestro took Jordan under his wing and a couple of spacefaring adventures turned them into best buddies - until Sinestro gave Jordan reason to question their entire friendship.

Under current continuity, Jordan learned that Sinestro was ruling over the people of his homeworld with a despotic fist, and so he reported him to the Guardians and had Sinestro banished to the Antimatter Universe. There, Sinestro became the first Yellow Lantern, using fear to his advantage, and set about building his Sinestro Corps - soon becoming not just Hal Jordan’s greatest rival, but the greatest threat to the Green Lantern Corps - period.

Prior to the tragedy that would come to define Bruce Wayne's life, his childhood best friend was Thomas Elliot. But young Tommy secretly harbored great hatred for the Wayne family because Bruce’s father had saved Tommy’s mother from the near-fatal car collision that claimed her husband - a mishap that Tommy engineered!

Elliot became a surgeon, but a chance encounter with the Riddler led to him to the discovery that Bruce Wayne and Batman were one and the same. Seeking revenge, Thomas took on the supervillain identity of Hush and started pulling strings in the background of Gotham, doing everything he could to make the Dark Knight's life a living hell.

Batman eventually figured out Thomas's secret identity and defeated his old pal, but Hush has returned time and again to cause trouble, with his most notable scheme involving the literal removal of Catwoman’s heart from her chest.

To call Reed Richards and Victor von Doom best friends would be a major misnomer. Victor always disliked Reed, and Reed’s best friend was always Ben Grimm. But it’s also fair to say that, as far as their college careers are concerned, Reed was Victor’s only real friend in the world. The two constantly traded barbs, but also advice, and at one point even went on a time-hopping adventure together with Reed’s father. 

Then, that fateful experiment-gone-wrong occurred, Victor was horrendously scarred, and he blamed Reed - despite Reed having warned him of the dangers of his endeavors. Victor proceeded to travel the world, adopt a mystical suit of armor, become Doctor Doom, and take over the nation of Latveria, becoming not just the Fantastic Four’s greatest rival, but possibly the greatest threat to the Marvel Universe as a whole.

Through it all, however, Reed has remained one of the few people to ever care about Victor, and still might be considered a borderline friend despite their many universe-defining conflicts. These days, von Doom is far more likely to pal around with Richards's super-genius daughter, Valeria, who might just be his true BFF.

As kids, Dick Grayson and Raymond McCreary were both performers in Haly’s Circus, but then Grayson’s parents perished and he was adopted by Bruce Wayne, destined for a superheroic life, first as Robin and later as Nightwing. Before all that, however, Dick had been preselected to be groomed as a Talon assassin for the Court of Owls; when he left the circus, that designation fell to Raymond.

The Court tormented Raymond, hoping to toughen him up enough to become a Talon, but they ultimately decided he wasn’t up to snuff and left him out in the wilderness to expire. Raymond survived, decided that Dick was to blame for all his troubles, and took up the costumed identity of Saiko to enact his revenge. Imagine his surprise when Dick turned out to already be a well-established superhero. Saiko attempted to destroy both Nightwing and Haly’s Circus, failed at both, and then chose to take his own life rather than live with his failures.