There was also a special Planet Hulk: Gladiator Guidebook publication by Anthony Flamini and the storyline's main writer Greg Pak, similar to the Official Handbook of the Marvel Universe detailing the characters, races and cultures within the storyline.
The storyline's main writer Greg Pak describes the origin of the ideas:
“The inspiration for sending Hulk to an alien planet where he'd battle monsters as a gladiator came from Marvel Editor-in-Chief Joe Quesada. I loved the idea from the minute I heard it, so I was blown away when they told me I had the gig and even more blown away when they basically cut me loose to create the whole world.”
He also drew from real-world history:
"I got inspiration for the story by reading about the real lives of gladiators in ancient Rome and from the stories of figures like Genghis Khan and more contemporary warlords, dictators, and political leaders. Sun Tzu's 'Art of War' and Joseph Campbell's 'Power of Myth' played a big role in helping me think through other aspects of the story."
The New Avengers: Illuminati
The Planet Hulk storyline begins in The New Avengers: Illuminati, which details Iron Man's attempts to form a coalition of heroes to deal with grave threats to Earth. Iron Man explains to the Illuminati how he plans to dupe the Hulk into destroying a "malfunctioning" weapons satellite which will launch the Hulk to a predetermined uninhabited planet to live out his remaining days. Namor objects to this plan and predicts that the Hulk will return and kill Iron Man.
Planet Hulk Prelude: Peace in our Time
Bruce Banner's attempt to live a solitary life in Alaska is undermined when a visit to a bar ends in his turning into the Hulk and apparently killing a bouncer. Nick Fury of S.H.I.E.L.D. contacts Banner and explains a HYDRA satellite designed to target and detonate a nuclear weapon anywhere in the world must be destroyed and, being organic and able to survive the vacuum of space, the Hulk should be able to do so without triggering the satellite's automatic responses. Banner agrees, but once he begins smashing it, he notices S.H.I.E.L.D. logos painted on the satellite. The Hulk is overwhelmed by the onboard weapon (codenamed "Godseye") which has decided to forego its normal source of solar radiation for the gamma radiation coming from the Hulk's body. The Hulk battles Godseye until it overloads. An automated S.H.I.E.L.D. shuttle arrives to retrieve the Hulk and, once he is aboard, the shuttle leaps into hyperspace.
Planet Hulk Part One: Exile
On the shuttle, a recording of Reed Richards and the other Illuminati explains to the Hulk their reasons for sending him away. However, a trajectory malfunction sends the Hulk to Sakaar, a planet inhabited by a humanoid-insect race. Representatives of the Red King, a Sakaarian emperor, salvage the shuttle and knock the Hulk out, showing that his invulnerability has been compromised.
Hulk is pitted against large creatures in gladiatorial combat and wins a pardon for himself and other slaves. After earning the title of "gladiators," the Hulk and his team are treated to a feast on a pleasure cruiser that is then attacked by the Sakaar Democratic Insurgency attempting to recruit the Hulk.
One of the members of the Hulk's team Elloe Kaifi joins the insurgents and encourages the Hulk to do the same. The Hulk refuses, figuring that the insurgents would, like the Illuminati, eventually betray him once he was no longer needed. The insurgent attack fails and Elloe is arrested. Her father, Lavin Skee laments and complains of the Red King's rule. The Hulk and his gladiator team then battle in the Imperial Crown City for the opportunity to become citizens if they survive three rounds in the arena. After the first round, the Hulk and his team declare themselves Warbound and swear loyalty to each other.
The Silver Surfer is then pitted against the Hulk. Like the Hulk, he was weakened by the transit to Sakaar. The Hulk succeeds in breaking the "obedience slug" used to control the Surfer. The Red King then orders the group to execute Elloe Kafi for their freedom. They refuse and the Silver Surfer uses his powers to destroy the slaves' obedience slugs. Having his freedom and feeling like he belongs, the Hulk decides to stay on Sakaar.
"World War Hulk" is a comic book crossover storyline that ran through a self titled limited series and various other titles published by Marvel Comics in 2007, featuring the Hulk.
The series consists of five main issues titled World War Hulk, with Greg Pak as writer and John Romita, Jr. as penciller, and three other limited series: World War Hulk: Frontline, World War Hulk: Gamma Corps, and World War Hulk: X-Men. It also ran through several extant Marvel comics series.
The plot is the culmination of a series of events that began with the Hulk being tricked into space by the Illuminati and a life model decoy of Nick Fury, the Hulk's subsequent exile seen in Planet Hulk and his imminent return to Earth to seek revenge on the Illuminati.
Blaming The Illuminati for the explosion of a space vessel they had constructed, leading to the deaths of his wife, his unborn child and millions of inhabitants of the planet Sakaar, the Hulk and his allies, the Warbound, come to Earth intent on revenge. First stopping at the moon, the Hulk defeats Illuminatus Black Bolt (later revealed as a Skrull impostor). The Hulk proceeds to Manhattan, New York City, where he demands the presence of the Illuminati and that the city be evacuated.
He travels to the nearby X-Mansion, home of the X-Men, where Illuminati member Professor X, absent from the decision to send the Hulk off-planet, admits he would have agreed to that but not to permanent exile. He offers to turn himself in to the Hulk, but the rest of the X-Men won't allow it. The Hulk defeats several teams of X-Men, and battles the Juggernaut, but leaves after learning of the mutant population's heavy losses during M-Day, believing that Xavier has suffered enough.
When the Hulk returns to Manhattan, the superhuman-operative team Gamma Corps battles him, but the Hulk convinces them they follow a false cause.
As the time limit for the evacuation has passed, the Hulk defeats Iron Man, destroying Stark Tower in the process, and fights Ghost Rider, who after realizing the Illuminati do not deserve vengeance, rides away. The Hulk and his Warbound next defeat the Avengers, Doc Samson and the Fantastic Four, including temporary members Black Panther and Storm. Fantastic Four leader Reed Richards' plan to simulate the Sentry's presence in order to calm the Hulk also fails, while Sue Storm and the U.S. President vainly attempt to have the real Sentry intervene. The Hulk attaches "obedience disks" to the defeated, imprisoned superheroes, preventing them from using their powers.
After a brief battle involving Hercules, Amadeus Cho, Namora, and Angel, the Hulk defeats General Thaddeus "Thunderbolt" Ross and a U.S. Army force. The Hulk then encounters Doctor Strange, breaking the sorcerer's hands in an attempt to prevent him from invoking spells. At Strange's Sanctum Sanctorum, Warbound members Hiroim and Elloe defeat Iron Fist, Ronin, and Echo. Strange mystically merges with a powerful old enemy, Zom, replacing his shattered hands with spiked maces, and defeats Hiroim.
An imprisoned Tony Stark (Iron Man) communicates with Dum Dum Dugan, acting director of the international espionage agency S.H.I.E.L.D. in Stark's absence. Stark reveals an emergency plan to engulf Manhattan in the Negative Zone, thereby annihilating all positive matter on the island, including the Hulk, should the heroes fail.
The Hulk and the Warbound transform Madison Square Garden into a gladiatorial arena. Meanwhile, he repels an assassination attempt from Scorpion, and a confrontation with the Initiative. He also defeats the Zom-possessed Dr. Strange and the demonic entity flees Strange to seek a new host, but after controlling Stark's Hulkbuster Armor it is defeated by the Renegades. Following speeches from supporters in the arena (including Tom Foster about how Iron Man was partially responsible for the death of his uncle at the hands of the Cyborg Thor clone) and the Hulk feeding a lion to a Demon Shrike (an alien creature), the Hulk arranges for Illuminati Doctor Strange, Iron Man, Black Bolt, and Mister Fantastic to fight a tentacled alien and later each other to the death, as a cheering audience watches. When the Hulk orders Mr. Fantastic to kill Iron Man, the Sentry, in response, leaves his mountainside retreat and speeds toward the arena.
The Hulk spares Mr. Fantastic and Iron Man, declaring his intention was for "justice and not murder", that nobody had to or would die, and declares that he plans to destroy New York City and leave the Illuminati to their shame. The Sentry arrives and attacks the Hulk, leading to a prolonged battle that leaves them spent and in their normal human forms when Hulk delivering the final punch, thus defeating Sentry.. Warbound member Miek impales the Hulk's longtime friend Rick Jones, and reveals he intentionally allowed the mass deaths on Sakaar, knowing that they were caused by former followers of the Red King. The Hulk reverts from his Bruce Banner alter ego, and he and the Brood No-Name batter Miek in retaliation. The Hulk, overwhelmed with rage from Miek's betrayal, unwillingly begins to release energy that threatens Earth. Illuminati member Reed Richards tells the Hulk that they will try to help him this time. The Hulk responds, "I will never forgive you and will hate you forever. Almost as much as I hate myself." The Hulk asks Tony Stark to stop him before he destroys the world, and the latter activates a series of satellite devices that opens fire and eventually leaves the Hulk in his Bruce Banner form, unconscious.
S.H.I.E.L.D. later imprisons Banner in a facility three miles underground, with the other Warbound members having been taken into U.S. military custody. Meanwhile, on Sakaar, the Hulk's presumed-dead son, Skaar, arises. His story is chronicled in the sequel Skaar: Son of Hulk.
World War Hulk Limited Series (Variant Covers included)