The character was introduced in 00 in Hulk , and has ties to the original Marvel character the Hulk, as the Red Hulk is created as part of a Super Soldier program by long-time members of the Hulk's supporting cast: General Thunderbolt Ross and psychiatrist Doc Samson. The A.I.M. creation MODOK, an old Hulk foe is also involved, as is a criminal think tank called "The Intelligencia". The character is described as "absolutely uninhibited, tactically intelligent"6 and "Everything the Green Hulk isn't, the Red Hulk is." Although possessing virtually all the abilities of the original green Hulk, the Red Hulk does not grow stronger with anger - instead emitting increasing levels of heat.
According to the newspaper USA Today, the Red Hulk was created to boost sales and create buzz in the lead up to the 00 film The Incredible Hulk. Loeb and McGuinness were initially working on a Hulk miniseries (as according to Loeb, "McGuinness came over from DC for one reason, and that's he wanted to draw the Hulk.") that would establish the Hulk as the strongest Marvel character. It was then that Joe Quesada proposed the idea for a red version of the Hulk with a secret identity. The identity of the Red Hulk is a mystery, both to the characters in the story and to the reading audience.0
Once the series was promoted, Marvel's insert booklets in Diamond Previews began referring to the Red Hulk character as "Rulk" to distinguish from the original Hulk character. Writer Loeb began using the term as of issue seven.
The title Hulk establishes that the character is very aggressive, as the Red Hulk murders Hulk foes the Wendigo and Abomination; destroys the Helicarrier of spy organization S.H.I.E.L.D.; defeats several Marvel heroes, and, after causing an earthquake in San Francisco, is finally defeated by the combined efforts of the Hulk and the thunder god Thor.
A 00 one-shot publication titled King-Size Hulk featured the Red Hulk, and was written by Loeb, with artwork by Frank Cho, Art Adams, and Herb Trimpe.
Issues seven through nine of the title were "split books", featuring two stories by Loeb, with Adams providing artwork for the first and Cho the second. The Red Hulk battles the female superhero team the Lady Liberators and, after tricking them, kidnaps member Thundra, and offers her an alliance. The Elder of the Universe the Collector teams the character with other villains (a team called the Offenders - an evil version of superhero team the Defenders) in a bid to prevent the original Hulk from reuniting with past love Jarella.
In the "Code Red" story arc, mutant assassin Domino investigates Rulk, observing him transforming from his human self. In response, Rulk pursues Domino with the help of Deadpool, Punisher, Elektra, and Crimson Dynamo XII, but comes into conflict with X-Force, a Red She-Hulk and Doc Samson.
In Fall of the Hulks: Alpha, it is revealed that MODOK was a part of a loose-knit cabal of scientists that included the The Leader, Doctor Doom, Mad Thinker, Wizard, Egghead, and the Red Ghost, which gathered the knowledge that MODOK eventually used to create the Red Hulk.6 In Fall of the Hulks: Gamma, Red Hulk fights and kills General Ross, apparently at the behest of Bruce Banner, with whom he has formed an alliance.
