Giant-Size X-Men #1 Main article: Giant-Size X-Men Krakoa was originally a very small island in the Pacific Ocean that was located close to where some nuclear bombing tests were done. The radiation somehow turned the island's ecosystem into a hive-mind entity.
In Giant-Size X-Men #1, The X-Men (then consisting of Cyclops, Angel, Havok, Iceman, Marvel Girl (Jean Grey), and Polaris) came to the island after Cerebro detected an unknown mutant there, and were captured by Krakoa, who used them as food sources. Cyclops was the only one able to flee, but doesn't remember what happened. Professor X decides to recruit international mutants to save his X-Men (namely Colossus, Nightcrawler, Storm, Sunfire, Thunderbird, Banshee, and Wolverine) and sends them to Krakoa. Cyclops' group of mutants pair off and after each pair encounter and defeat various aspects of the island, the new X-Men team finds the original X-Men, who are weakened from being fed upon by Krakoa for so long. At this point, it is revealed that it was the island itself that Cerebro had registered as a mutant, and Krakoa battles the new and old X-Men by forming a giant humanoid body out of its terrain. With a combination of psi interference by Professor X and energy blasts from Cyclops and Havok, Storm is able to supercharge Polaris' magnetic powers with bolts of lightning. Polaris interacts with the Earth's core and creates a magnetic pulse so strong that she is able to launch Krakoa into outer space. The X-Men - now counting thirteen members - are saved.
Later a "son of Krakoa" appeared. It was the result of a spore that was released from Krakoa as it was shot into space. Nightcrawler eventually defeated this "Vega-Superior" by tricking him into drowning himself.
Krakoa was apparently found and captured for study by the cosmic entity known as The Stranger, as seen when Quasar visited one of his 'laboratory worlds'. Krakoa was eventually freed as well as many of the specimens.
 X-Men: Deadly Genesis
Main article: X-Men: Deadly GenesisThe 2006 X-Men: Deadly Genesis storyline features a major retcon in which it is revealed that many of the elements in Giant-Size X-Men #1 were in fact deceptions and delusions created by Professor X to hide the major part of the story. Another team of young mutants, composed of Petra, Darwin, Sway, and the third Summers brother Kid Vulcan, from a parallel X-Mansion led by Moira MacTaggert, were sent to help the original X-Men. They managed to save Cyclops and returned him to Professor X. However Krakoa, no more intelligent than an animal, killed Petra and Sway and left Darwin and Kid Vulcan almost dead. Xavier had erased all records of the real events in Cyclops' mind, and altered the mutants' minds to cast the illusion of a speaking, sentient Krakoa.
 Manifest Destiny
Main article: X-Men: Manifest DestinySunspot's business partner tells the Young X-Men that his workers went missing on an uncharted island. This island turns out to be an offshoot of Krakoa.[volume & issue needed]
 Powers and abilities
In its original depiction, Krakoa was an immensely powerful being. It could manipulate its flora and fauna at will and possessed incredible psi powers, rivaling those of Professor X; indeed, it was capable of subtly manipulating his mind from a great distance to prevent him contacting experienced heroes for help. After the revelation of the events surrounding Vulcan, it was revealed that Krakoa was little more than an animal-like system whose intelligence was merely survival instinct.
 Other versions
 Amalgam Comics
Krakoa the Living Dinosaur Island from Amalgam Comics.For Amalgam Comics, Krakoa was combined with Dinosaur Island to form Krakoa the Living Dinosaur Island. The insane mutant hater Dr. Will Magnus and his Sentinel robots used Krakoa as their base of operations before their location was discovered by Magneto.
 Ultimate Krakoa
In the Ultimate Marvel continuity of Ultimate X-Men, Krakoa was reimagined as an apparently normal island near Genosha, on which TV mogul Mojo Adams hosts his gruesome reality TV show Hunt for Justice, in which mutant felons are hunted to death. It is where Ultimate Deadpool takes Spider-Man and the X-Men in the Deadpool arc of USM.[volume & issue needed]
 What If?
Krakoa was featured in various versions of What If?:
- In "What If the X-Men Died on the First Mission," Polaris demagnetizes Krakoa only for the featured X-Men to not be able to get off in time.[volume & issue needed]
- In "What If an All New, All Different X-Men Never Existed," the original X-Men had never disbanded and were able to defeat Krakoa easily.[volume & issue needed]
- In What If? Deadly Genesis, Vulcan and his team make their way through the island, surviving its assault. Vulcan becomes separated from the group and finds the captured X-Men. After accidentally killing them all in a panic, Vulcan escapes the temple and, with the rest of his team, the island itself. Krakoa is then jettisoned into deep space, where it remains untouched for years until being discovered by the Silver Surfer. There, Sway finds a time pocket and uses her powers to replay the events of Vulcan's killings. After confronting and disabling him of his powers, Professor Xavier banishes Vulcan to the island, where he is forced, as punishment, to replay the transpired murders of the X-Men every time he requires food.[volume & issue needed]
- In the story What If? Rise and Fall of the Shi'ar Empire Krakoa is resurrected by a power-mad Vulcan using the Phoenix Force, with a battle between him, Rachel Summers, Havok, Cyclops, and Cable taking place on it.[volume & issue needed