The Hulk is the strongest of Marvel superheroes, but one moment redefines the limits of his strength. Bruce Banner’s famous gamma-irradiated alternate persona has theoretically limitless strength, but the full extent of it is rarely shown. In one 2011 issue of Incredible Hulks, Hulk’s full strength is finally unleashed, and its context also reveals a key detail about Banner’s Hulk persona.
In issue 634 of Incredible Hulks, by Greg Pak and Paul Pelletier, The Hulk is trapped in the Dark Dimension, where he prepares to battle a multitude of enemies. The Hulk warns his allies to return to Earth because he will not only use his “Worldbreaker” form but also, for the first time, truly not hold his strength back, as he has in all previous fights. True to his word, the Hulk unleashes an attack that vaporizes his enemies instantly, obliterating Armageddon, Bi-Beast, and Wendigo (three of Marvel's toughest villains), and shattering the planet on which he stands.
Hulk's Full Strength Is a Planet-Killer
Among the Hulk’s most famous storylines is World War Hulk, which contains some of the green behemoth’s most impressive feats. In the story that saw the debut of Hulk’s “Worldbreaker” form, the Hulk goes up against some of the Marvel universe’s heaviest hitters, including the Avengers, the Fantastic Four, the X-Men, and even Doctor Strange and Black Bolt, defeating all of them. It's only once he faces the Sentry that the two godlike beings fight to a standstill. However, Hulk explicitly confirms that "even in the war in New York ... I was holding back." It turns out he has to, because when Hulk uses his full strength, the planet itself can't survive. Hulk is only willing to go all-out in this fight because he finds himself in a demonic dimension where they are no innocents. It's the only time he hasn't had to control himself to protect the people his fight would otherwise destroy.
Hulk's Strength Has No Limit
It's confirmation that no matter how angry the Hulk gets, he does care about innocents, and that even when seeking revenge for his murderered wife and child, he still wasn't willing to sacrifice Earth to get satisfaction. Fans have seen Hulk destroy a planet since - in The Immortal Hulk - but only once he had been possessed by the Cthulhu-esque One-Below-All and consumed Galactus' power. The fact that Hulk can break a planet in one hit, purely under his own power and directed by his own personality, is a mind-blowing redefinition of all his other feats of strength. Hulk may be a rampaging rage monster, but it turns out he's always been holding himself back, and to a truly extreme degree.
Considering his seemingly savage strength and unbridled rage, it is easy to doubt that the Hulk is truly a superhero. One can easily mistake Hulk for a blunt tool used by Bruce Banner, but for all his anger, Hulk is a hero who cares about how his actions affect innocents. The Hulk wants to be left alone, but he will go out of his way to help others and, as shown in Incredible Hulks, limit his full strength to protect innocent lives, making him as much a superhero as his Avengers teammates.