When Red Hulk came to Galactus, he tried to attack him, but Galactus was merely insulted by his blasphemy and took away the Power Cosmic from him. He then sent Red Hulk back and threatened to retaliate by destroying the Earth next. Tired of taking orders from Grandmaster, Ross killed him.
The Hulk would win in a fight against Red Hulk. This is because his powers and abilities are amplified the angrier he becomes, and he'd, therefore, easily dispatch Red Hulk at his peak rage level. Additionally, the Hulk is stronger, faster, more invulnerable, more intelligent, and a better combatant than Red Hulk.
However, the 2010 "World War Hulks" story line reveals that the Red Hulk is Thunderbolt Ross himself, the Red She-Hulk his daughter Betty, and the Ross who was "killed" was a Life Model Decoy used to convince the world that he had died.
Hulk uncovered Red Hulk's condition of the angrier he gets, the hotter he gets, and guessed it could be a weakness. Hulk let his opponent strike him repeatedly until the heat became too intense for the Red Hulk. He became unbalanced, and Hulk was able to finish him off quickly.
Weaknesses. As Ross, he is as vulnerable as any human. However he can overcome this weakness with his will-powered transformation into Red Hulk. As Red Hulk, he displays a notable weakness against bladed and sharp objects.
Abomination – Emil Blonsky. A gamma-spawned monstrous powerhouse. The Hulk's primary physical rival.
Titan, the Hulk's most deadly form, takes control of the Green Goliath and ruins a planet full of creatures that look like him in Marvel's Hulk #13.
In the debut, Lee chose grey for the Hulk because he wanted a color that did not suggest any particular ethnic group. Colorist Stan Goldberg, however, had problems with the grey coloring, resulting in different shades of grey, and even green, in the issue.
Red was part of a film crew that was transported to Asgard by Loki. And at Loki's behest, Red took Thor's Belt of Strength and bathed in the Fires of Geirrodur before claiming Thor's Iron Gloves. The gloves were the key, since they allowed Red to lift and wield Mjolnir without being worthy.
Onslaught - The Death Of The Marvel Universe
During that ultimate sacrifice, Hulk also died. Jean Grey shut down Bruce Banner's brain, turning Hulk into a savage. The two ended up separated, and Hulk ended up in an irradiated cocoon, one that killed Hulk completely, which led to a new Hulk being horn.
The Orange Hulk was part of the Black Legion who served Weapon Omega. He was presumably constructed by McCoy or the Sugar Man in their genetic recombinant vats. He defended the Apocalypse ship in Manhattan and attacked the last human settlement where the X-Men fell.
Introduced in 2012's Avengers #24, the Purple Hulk is Norman Osborn, aka Spider-Man villain the Green Goblin. After the Skrull attack known as the Secret Invasion destroyed trust in existing institutions, Norman Osborn managed to replace Nick Fury's S.H.I.E.L.D. organisation with his own fascistic H.A.M.M.E.R.
Characters like Doctor Strange, Thor, and the Hulk are all more powerful than Ghost Rider. Ghost Rider is a powerful character, but he is not the most powerful character in the Marvel Universe.
Now, he isn't stronger than the Hulk, but he has an additional power - he can absorb radiation (and also melt things with his eyes for some reason). This, then, gives him a HUGE advantage in a fight against the Hulk.
Due to the gamma radiation that birthed him, his skin is nearly indestructible and takes massive force to break. Throughout Hulk's many on-screen fights, he has only bled twice, and both circumstances prove it takes a unique set of variables to accomplish that.
Thanos is a mutant member of the race of superhumans known as the Titanian Eternals. The character possesses abilities common to the Eternals, but amplified to a higher degree through a combination of his mutant–Eternal heritage, bionic amplification, mysticism, and power bestowed by the abstract entity, Death.
Skaar is a fictional character, a comic book superhero appearing in American comic books published by Marvel Comics, usually as a supporting character in stories featuring his father, the Hulk, who conceived Skaar with the extraterrestrial Caiera during the 2006–2007 "Planet Hulk" storyline.
Apocalypse makes his way into this position on the list because he is technically stronger than the Hulk. He also has a multitude of other abilities, including telepathy, telekinesis, and shapeshifting. And that's just touching the surface of his powers.
Whether it was magic-wielding sorcerers like Doctor Strange or entire teams like The Avengers, almost nothing can get in Hulk's way when he's on a rampage. Though he has beaten the best of the best, only his biggest victories left readers stunned at the sheer power of Bruce Banner's alter ego.
Bruce Banner's deepest fear since becoming the Hulk is losing control of his emotions, which has been evident in his transformation into his bloodthirsty alter-ego, Kluh, in the AXIS storyline. Kluh's extreme ferocity even alarmed the Hulk himself, a testament to the danger he poses.
Weakness: RAGE
While Hulk's rage makes him almost completely invulnerable and the strongest being in the entire universe, it also is a huge weakness. The increase of his power when in rage mode is massive. However, at the same time, he also loses almost all his intelligence when he grows angrier.
The Hulk has been called the strongest Avenger given his unparalleled, planet-shattering strength, but within the 2099 future of Marvel and DC's crossover universe, the Hulk would be considered the weakest Avenger (for one specific reason).