Planet Hulk

When a Gamma bomb causes the Hulk to lose control and attack Las Vegas,[2] the Illuminati decide the Hulk is too dangerous to remain on Earth.[3] They trick him into entering orbit to destroy a rogue satellite, and then use a shuttle to jettison him from the solar system. They intended for him to land on a peaceful planet, but the shuttle passes through a wormhole on its way.[4]

As Hulk listens to a recording from the Illuminati explaining their actions, his shuttle crashes on the planet Sakaar. Weakened from the crash, Hulk is fixed with an obedience disk and taken into slavery. He is forced to fight gladiator battles for the planet's emperor, the Red King.[5] Hulk forms a "Warbound" pact with his fellow gladiators Miek, no-name Brood, Elloe Kaifi, Lavin Skee, Hiroim and Korg.

Hulk becomes a popular hero for his actions in the arena, and a group of insurgents try to recruit the Hulk to their cause.[6] The Hulk declines, but Elloe chooses to go with the rebels.

During their next gladiator fight, Lavin Skee is killed.[7] As the others come closer to winning their freedom, the Red King's lieutenant, Caiera, arranges for them to fight the Silver Surfer, who is also controlled by an obedience disk. During the battle, the Hulk breaks the Silver Surfer's disk, freeing him. The Silver Surfer then destroys all the obedience disks of everyone in the arena. As he leaves Sakaar, he offers to return Hulk to Earth. Hulk chooses to stay behind.[8]

The Hulk and his Warbound, now on the run from the Red King, are hunted by Caiera. As they travel through villages, Hulk finds followers who believe he is the foretold savior, "Sakaarson". Hulk denies this title. Caiera finally confronts the Hulk, but their battle is interrupted by an invasion of "spikes" that cause monstrous mutations and death to anyone they touch. Caiera calls the Red King for assistance and learns that he ordered the spikes to be deployed there. Horrified at what her king has done, Caiera joins the Hulk.

Hulk leads a raid on the Red King's capital, culminating in a one-on-one battle between the two of them. The Red King is defeated, and Hulk is named the new king. He takes Caiera for his wife, and the two are able to broker peace among the various conflicts which had festered under the Red King. Caiera becomes pregnant with Hulk's child.[9]

Meanwhile, the shuttle that brought Hulk to Sakaar is being turned into a monument. As part of its self-destruct sequence, the antimatter warp core engine detonates in a massive explosion. The whole city is destroyed, and Caiera dies. Enraged and blaming the Avengers who built the shuttle for the damage, Hulk and his Warbound leave Sakaar and head for Earth.[10]

Arriving on Earth, Hulk and the warbound begin World War Hulk.[11]

Sakaar rebuilds after the explosion with the help of Hulk's two surviving sons, Skaar and Hiro-Kala.[12]

A special issue of What If? featured three alternate versions of Planet Hulk:

• The first story shows the Hulk sacrificing himself to save Caiera by throwing her into the planet's orbit. Caiera survives and upon returning to Sakaar, she is met by the Warbound who learn of the Hulk's death while Miek is killed trying to find the Hulk. Caiera absorbs all of Sakaar's energy, becoming more powerful than ever, before heading to earth with the Warbound. Doctor Strange and the Sentry intercept the ship, but Caiera uses the captured Black Bolt to vaporize them. Caiera then attacks the Fantastic Four, killing Reed Richards and eventually Iron Man. The Avengers attempt to fight her, but Caiera easily defeats them as well. Caiera then proceeds to kill the remaining heroes, but Hiroim stops her, pointing out that the "guilty have paid" and that if she wipes out everyone on the planet, no one will be left to honor the Hulk. Caiera agrees to stop fighting, but remarks that "they'll wish they were dead". Twenty-one years later, Caiera now rules earth and has enslaved humanity, while her son, Skaar, has erected a colossal statue of her late husband.
• The second story involves the Hulk landing on the planet that the Illuminati had promised him, instead of Sakaar. The Hulk begins to coexist with the creatures and finds life on the planet to be more peaceful than on earth, whilst being involved in a personal struggle between himself and Bruce Banner. Years pass, and the Hulk's actions have caused the planet's evolution to take a turn and centuries later, intelligent, humanoid beings now inhabit the planet and most consider stories of the Hulk to be only a legend. One young boy, however, sees the Hulk, who is now smaller, more "native" to the world, and at peace.
• In "What If Bruce Banner Landed on Sakaar Instead of the Hulk", Hulk's shuttle lands on Sakaar, and, thinking this is a peaceful planet, Hulk regresses to Bruce Banner, only to be killed shortly after. A year later, Reed Richards lands on Sakaar to bring Banner back to earth, but is killed as well. Ten years later, a number of heroes have been killed on Sakaar, with Hawkeye being the most recent victim.

The 2015 Secret Wars crossover included a miniseries titled "Planet Hulk" written by Sam Humphries and penciled by Marc Laming. It follows a variation of Steve Rogers and a variation of Devil Dinosaur as they fight their way through the Battleworld domain of Greenland, a region filled with an assortment of Hulks.[13]

In an alternate Marvel Universe, Dr. Bruce Banner (who has no alter ego) owns a large technology business known as Bannertech. The headquarters is a city of the future where Amadeus Cho (who works at Bannertech), performs unauthorized gamma experiments on animals. Dr. Banner and Amadeus are alerted by S.H.I.E.L.D. that the Gamma Bomb in S.H.I.E.L.D.'s possession has been stolen and launched by A.I.M. Bruce attempts to evacuate the city of the future whilst Amadeus tries to hijack the bomb. The bomb ultimately crashes into the Bannertech tower, destroying it and catching evacuating employees in its blast radius. Dr. Banner and his employees are turned green, but they are relieved that they are alive. Amadeus is not seen again. The employees and Dr. Banner suddenly mutate into various Hulk creatures. When the various Marvel universes collide, a section of this Earth including the inhabiting Hulks become the region of Battleworld known as Greenland. Sometime after the creation of Battleworld, Doctor Doom has his Thor Corps perform a mission for him. As they fly over the Mud Kingdom in Greenland, they are attacked by the Hulks who live there. The Hulks' primitive weapons anger the Thor Corps who stop the attack by destroying the Hulks' homes. The Thor Corps then leave as they were told to contain battles, but not to interfere. Meanwhile, in God Emperor Doom's Killiseum in Doomstadt, Steve Rogers and Devil Dinosaur win their twelfth fight. Whilst being congratulated by Arcade, they attempt to interrogate him to find where Bucky Barnes currently is. Their attempt fails and Steve is summoned by God Emperor Doom. Sheriff Strange offers Steve a chance to live on behalf of God Emperor Doom. Steve must travel to Greenland, kill the Red King, and rescue Bucky from him. Steve takes Devil Dinosaur with him and they are teleported by Doctor Strange to Greenland. Upon arrival, they are meant to meet with an operative. However, they are attacked by gamma-irradiated bugs. Steve and Devil Dinosaur are saved by a Hulk named Doc Green who fires a powerful laser cannon killing the bugs.[14]

Upon getting acquainted with the Captain and the Devil after they woke up, Doc Green agrees to become their guide in Greenland to help them navigate it and rescue Bucky from the Red King. During a flashback in an unknown kingdom, the Captain and Bucky are racing through the rubble in the streets of a war-torn city. A missile blows up the ground in front of Bucky. Steve digs Bucky out of the rubble. Steve picks up Bucky and starts to carry him to safety. Bucky says that they need to get underground. Bucky then suggests that he and Steve enlist to fight. Steve comments that they are both beanpoles and have no business fighting. Bucky points to a picture of The Falcon as Captain America in a propaganda poster for the Super Soldier program. Steve says it is nothing but a pipe dream. On their way to the Mud Kingdom, Doc Green saves the Captain and Devil from a Hulk-Eating Plant. The Captain and Doc Green were then attacked by Bull Hulks and separated from Devil. Upon ending up in the Gamma Lake after escaping into the river and going over the waterfall, the Captain and Doc Green were attacked by a giant aquatic creature called a Sea Hulk that grabs the Captain with its tentacle. Doc Green then quotes: "There you are. Come out and play".[15]

As Doc Green tried to get to the Captain, the Devil showed up and attacked the Sea Hulk, killing it by biting off part of its neck during the fight. The incident put them off course, leaving them with two choices: circle back around the Fang Mountains which would take three days or cut straight to the Mud Kingdom by going through the Barrens of the Tribal Hulks where the Tribal Hulks dwell. The Captain decided to go through the Barrens of the Tribal Hulk as it was the faster route. In their way through the Barrens, they saw a wall made of the skulls of the people who died in the civil war between the Mud Kingdom and the Tribal Hulks. Doc Green said that the gamma only revealed what's already within each living being: an obsession with war and violence. It was the reality everyone denied. He then began to mock the Captain by saying it would be no different with him if he got corrupted by gamma as he was already doing God Emperor Doom's dirty work. But Captain said he wouldn't as he planned to find and free Bucky without killing the Red King. As a storm approached them, they took shelter inside a cave and were attacked and captured by the Tribal Hulks.[16]

The Captain was taken by the Tribal Hulks to the Mud Kingdom to be sold as a slave, but was rescued by Doc Green before the Tribal Hulks could do so. After they got to the top of a structure, Doc Green pointed at the Red King's castle where Bucky was being held. Doc Green warned the Captain that it was not like the time when he and Bucky stole pies from grandma Hubbard. Surprised, the Captain asked him how he did know about that and who he was before he turned into a Hulk. Before Doc Green could answer, the Devil returned to help the Captain. With his help, the Captain invaded the castle and confronted the Red King. The Captain told him about his mission, but said that if he released Bucky, he would then spare his life. The Red King revealed that God Emperor Doom had lied to him and that he had sent Bucky's head to Doomsgard a month ago. He then grabbed the severed bionic arm of Bucky and said that Bucky wasn't his prisoner, but his trophy.[17]

The Red King then tried to convince Rogers to join his army to take God Emperor Doom down, as he was the one responsible for Bucky's death; however, he was attacked and killed by Rogers instead. Doc Green showed up afterwards, congratulating the Captain for the completion of his mission. With the Red King dead, Doc Green would take his place and rule the Mud Kingdom as God Emperor Doom had planned. The Captain started to argue with him as he knew that Bucky was already dead and manipulated him into thinking otherwise in order to get the mission done, while Doc Green mocked him by having succumbed to the Hulk inside himself just like him. Rogers said he wasn't anything like Doc Green. In order to prove him wrong, Doc Green returns to his human form of a Steve Rogers from a domain similar to the one the Captain came from where his Bucky died and he became a Hulk. Doc Green taunted a confused Captain about how Bucky made him weak and because of his loyalty to him he would leave him to rule the Greenland. The Captain responded that Bucky had made him brave enough to do what must be done and killed Doc Green. The Captain then threw the severed head of the Red King in front of the Tribal Hulks which ended the battle between them and Devil. After grieving their companion's death, the Captain and the Devil left the Mud Kingdom behind.[18]

• Parts of the "Planet Hulk" storyline were incorporated in The Super Hero Squad Show episode "Planet Hulk".
• In the Hulk and the Agents of S.M.A.S.H. episodes "Monsters No More" and "Planet Leader," Hulk, She-Hulk, A-Bomb, Red Hulk and Skaar are transported to Sakaar. Leader fills in the role of the Red King. Miek, Elloe Kaifi, Hiroim, and Korg are shown to be slaves under Leader's control thanks to the control discs while the inhabitants of Sakaar praise Leader to be their hero. The Agents of S.M.A.S.H. lead the slaves in a rebellion and exposed Leader.

• The Lionsgate adaptation of Planet Hulk is based on this storyline, and was released in February 2010.[19] The film differs from the comic in some plot point and characters like No-Name not appearing and Beta Ray Bill appearing instead of Silver Surfer.
• The Sakaarans appear in Marvel Studios' film Guardians of the Galaxy.[20]
• The 2017 film Thor: Ragnarok, set in the Marvel Cinematic Universe, adapts elements of the Planet Hulk story. In the film, Grandmaster is the ruler of Sakaar instead of Red King. Additionally, Hulk became a gladiator willingly, where in the comics he does so reluctantly (although some of the circumstances of his arrival on the planet are adapted to fit Thor's story). Both of them managed to lead a slave revolt before returning to Asgard to stop Hela.[21]

• Hulk's experience on Sakaar is referenced in dialogue in Marvel: Ultimate Alliance 2 and Ultimate Marvel vs Capcom 3.
• Hulk's gladiator armor appears as a playable skin via downloadable content in Marvel vs. Capcom: Infinite.

• A prose novelization of Planet Hulk, also written by Greg Pak, has been released. [22]