Possessor of the Power Cosmic:
Galactus was originally the explorer Galan from the planet Taa, which existed in the pre-Big Bang universe. When a cataclysm gradually kills all other life in his universe, he and other survivors leave Taa on a spacecraft and are engulfed in the Big Crunch. Galan does not die, however; he is transformed by bonding with the Sentience of the Universe. He gestates for billions of years in the universe which formed after the Big Bang, emerging as Galactus. A Watcher (Ecce) sees Galactus' birth; although he recognizes his destructive nature, he chooses not to kill him. Fully awake, Galactus is so hungry that he consumes the nearby planet of Archeopia. This planet is the firs of many, since Galactus must consume their life energy for sustenance. In memory of his dead home world Taa and the first planet to fall prey to his hunger, Galactus constructs a new "home world" (Taa II).
He later becomes involved in a civil war among the Proemial Gods, who came into being during the universe's infancy as caretakers of the cosmic balance. After a faction of the gods (led by Diableri of Chaos) tries to remake the universe in their image, Galactus kills Diableri and imprisons two other rebel gods (Tenebrous and Aegis) in the Kyln.
Galactus is driven to create a being in his own image, Tyrant; Tyrant rebels, and after a battle they part. Galactus decides to empower others as heralds to find worlds for him. Unhappy with his first herald, the Fallen One, he dismisses him and later recruits Norrin Radd as the Silver Surfer.
After making his way to Earth, Galactus is defeated by the Fantastic Four, Uatu the Watcher and the rebellious Silver Surfer after they retrieve the Ultimate Nullifier from Galactus' possession. Galactus leaves Earth, vowing that he will never try to consume it again; however, he relegates the Silver Surfer there for betraying him. He later returns for his former herald, but the Surfer is unrepentant and chooses to remain on Earth. Thor sees Galactus when the entity is in conflict with Ego the Living Planet, and discovers his origin.
Returning to Earth, Galactus again tries to re-enlist the Silver Surfer. The Fantastic Four and the Surfer defeat Galactus' herald, Air-Walker; Mr. Fantastic reprograms Galactus's ship to travel to the Negative Zone, said to contain many uninhabited worlds to consume. Thor and Olympian ally Hercules see Galactus when his next herald, Firelord, travels to Earth to be free of his master. Galactus frees Firelord when Thor presents Galactus with the Asgardian Destroyer to animate and use as a herald.
Galactus conflicts with the High Evolutionary when he tries to devour Counter-Earth, but he is transformed into harmless energy after attempting to devour the planet Poppup. Returning to his normal form, Galactus is sought by the Fantastic Four to help stop a new cosmic threat (the Sphinx). Mr. Fantastic offers to release Galactus from his vow to avoid Earth if he helps defeat the Sphinx. Galactus agrees, if the Fantastic Four recruit Terrax as a new herald. The heroes succeed, and the newly-empowered Terrax leads his master to Earth. Galactus finds the Sphinx in Egypt, defeats him and retreats when Mr. Fantastic threatens to use a fake Ultimate Nullifier.
Galactus is fooled by the Galadorian space knight Rom into trying to devour the Black Nebula, home of the Dire Wraiths. The devourer is repelled by the Wraith Sun weakened, he pursues the rebellious Terrax to Earth and strips him of power. Galactus is saved by the Fantastic Four and the Avengers and acquires another herald, Nova.
He destroys the Skrull homeworld, and discusses his role in the universe with fellow cosmic entity Death. Mr. Fantastic is captured for saving Galactus' life, and is tried by aliens who are remnants of races annihilated by Galactus' hunger. During the trial the cosmic entity Eternity—the sentience of the Marvel Universe—intervenes, allowing all present to momentarily become one with the universe. This lets them understand that Galactus is part of the cosmic order, despite the loss of whole races. After the encounter no one can remember why Galactus is necessary, but they know that he is.
During the Secret Wars, Galactus tries to consume Battleworld to have his insatiable hunger taken away by the Beyonder but his plan is foiled by Dr. Doom. He grants clemency to the Surfer, who helps his former master against the Elders of the Universe and the In-Betweener's schemes. Galactus helps the cosmic hierarchy in a war against the mutant Eternal Thanos, who had the Infinity Gauntlet.
When Nova is conscience-stricken at causing the death of billions of aliens Galactus takes on a new herald, the bloodthirsty Morg. Tyrant returns; despite capturing the Surfer, Morg and several other cosmic-powered aliens, he is thwarted by Thanos and destroyed when Morg uses the Ultimate Nullifier.
Galactus decides, with help from new herald Red Shift, to only devour the energy of living beings; this brings him into conflict with alien races and Earth's heroes. During a final confrontation near the home world of the Shi'ar, the Silver Surfer turns Galactus' siphoning machines on him. Galactus starves and dies, taking the form of a star.
The death of Galactus allows the entity Abraxas (a metaphysical embodiment of destruction, and the antithesis of cosmic entity Eternity) to emerge from imprisonment. He wreaks havoc across thousands of alternate universes, killing every incarnation of Galactus that he encounters. Abraxas is thwarted when the children of Reed Richards, Franklin Richards and Valeria Von Doom, exhaust their powers to restore Galactus; Mr. Fantastic uses the Ultimate Nullifier to reset reality, preventing Abraxas' escape and destruction.
Conscience-stricken, Galactus tries to rid himself of his hunger by feeding on the power from the Infinity Gems but is tricked into releasing the Hunger, which feeds on entire universes. The creature's access is sealed, with Thanos' help.
When an alien race develops a technology making planets invisible to Galactus, he empowers the Human Torch (who has traded powers with the Invisible Woman) as an unwilling herald to locate the planets. The Fantastic Four and Quasar are able to free the Torch by changing Galactus back into Galan.
Galactus consumes Beta Ray Bill's Korbinite home world and reveals a new herald: Stardust. When the Negative Zone villain Annihilus launches a war on the universe, one of his first attacks destroys the Kyln and frees Tenebrous and Aegis. Sensing their release, Galactus temporarily releases Stardust from service and reemploys the Silver Surfer as his herald. Aegis and Tenebrous find and defeat the Silver Surfer and Galactus, delivering them to Annihilus.
Annihilus binds Galactus, and plans to use his energy to destroy all life in the universe. Drax the Destroyer frees Galactus, and after Galactus teleports Drax to safety unleashes a blast which destroys most of Annihilus' forces. Galactus accepts Stardust as his herald again, with Silver Surfer. Seeking a final confrontation with Aegis and Tenebrous, Galactus sends the Silver Surfer to locate them. The Surfer finds them and engages them in battle, drawing Aegis and Tenebrous into the barrier between the universe and the Negative Zone (which destroys them).
After an encounter with Epoch, Galactus consumes the planet Orbucen. He and Stardust again come into conflict with Beta Ray Bill when a distraught Bill seeks vengeance against Galactus for the destruction of the Korbinite home world. Feeling empathy for the only survivor of a destroyed planet, Galactus creates a female Korbinite for Bill.
Galactus is drawn to the planet Sakaar and devours it, earning the enmity of Skaar and Hiro-Kala. Hiro-Kala poisons Galactus with the Old Power, a synthesized form of the Power Cosmic.
The Silver Surfer finds the body of a future Galactus under New York City, and summons the present Galactus (who confronts Mr. Fantastic) to Earth. Mr. Fantastic explains that in the future, the heroes on a dying Earth had killed Galactus to escape to the present with time travel. When he discovers that those heroes live on a planet called Nu-Earth in the present, Galactus destroys it (and its inhabitants) in retribution.
A tear in the fabric of space caused by the Annihilation Wave and other interstellar conflicts allows the extra-universal forces of the Cancerverse (a universe without death) to invade. Galactus, the Celestials and the resurrected Tenebrous and Aegis combat the powerful Cancerverse weapon, the Galactus Engine.
In the "Chaos War" storyline Galactus is teleported to Earth by Hercules to help fight the Chaos King, a metaphysical embodiment of oblivion and another antithesis of Eternity. While Hulk and his allies (the God Squad, Alpha Flight and the surviving Dead Avengers) fight Amatsu-Mikaboshi's forces, Amadeus Cho and Galactus work on a machine which will move Earth to the sealed-off continuum.Heralds of Galactus
Fallen One (deceased)
Silver Surfer (dismissed, recommissioned twice)
Gabriel the Air-Walker (deceased)
Terrax the Tamer (dismissed)
Nova (Frankie Raye) (presumed deceased)
Morg the Executioner (deceased)
Red Shift (deceased)
Human Torch (dismissed)