The Hulk May Be Strong, But One Marvel Villain Knocked Him Out With a Single Punch
Marvel's Incredible Hulk is wildly considered to be one of the strongest beings in the universe, and certainly the strongest on planet Earth, almost always defeated through cunning, trickery, and careful planning, as opposed to brute strength. Shockingly, the villain Madman - who is actually the brother of Hulk's gamma-powered rival Leader - once defeated Hulk with one punch, proving that there are some creatures on Earth capable of going toe-to-toe with Banner.
Hulk's strength is based on his anger, which knows no bounds, but that doesn't mean he can't be beaten, with characters like Thor, Hercules, Wolverine, and Spider-Man taking the rampaging antihero down, using their unique skills and powers.
Madman, or Philip Sterns, debuted in 1989's Incredible Hulk #362, and remained a persistent thorn in Bruce Banner's side for many years, not only fighting the Hulk directly but also hatching many schemes to poison or eliminate his perceived rival, until he died in 2013's Thunderbolts #6.

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Madman Was Able To Knock Out Professor Hulk In One Punch
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The man who later became Madman first met Bruce Banner while studying alongside him at CalTech, quickly developing a deep jealousy towards the gifted scientist that devolved into obsession as time went on. After Banner became the Hulk it seems that Madman became determined to become a Hulk in his own right, injecting himself with many doses of gamma radiation over a long period of time. This gamma experimentation turned Philip into Madman, capable of transforming his size and density into a monstrously strong being, but also fracturing the man's mind, leading to a full mental break.

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Madman attempted to kill the Hulk many times, most notably when he injected the Hulk with a poison that made him progressively weaker, while Bruce was forced to battle much of his Rogue's Gallery of villains. If not for the unlikely intervention of Samuel Sterns, the villainous Leader and Philip's brother, the Hulk would not have survived. While they thought Madman has passed away himself, he later appeared as part of the Red Skull's New World Order and helped to create the monstrosity Piecemeal. When Hulk was forced to fight Piecemeal in Incredible Hulk #407, Madman came upon the scene and using the element of surprise knocked Bruce out with one punch. While Bruce was in his Professor Hulk form, a less powerful version of Hulk, it is still incredibly impressive that Madman was able to use physical strength to take down Hulk.
The Leader Was Terrified Of His Madman Brother
After Madman's death he Leader tortured him in his afterlife
The Leader was petrified of his brother's power, and madness, astounded at his ability to take on the Hulk directly, since Samuel has always needed to use his telepathy and gamma-based psychic abilities to assault the Hulk. After Madman's gruesome death - the villain's head exploded after his brother whispered the secret of Gamma Radiation to him - Leader made a deal with Mephisto to watch Madman be tortured in Hell every time Leader had lunch. A terrifying ending for a man capable of taking on the Hulk.
While the Hulk has been defeated many times in the past, it is rare for an enemy to beat him using only physicality, something that Leader's deranged brother Madman was able to do in just one punch.

- Created By
- Stan Lee, Jack Kirby
- First Appearance
- The Incredible Hulk (1962)