Formerly a mortal man, he is a cosmic entity who consumes planets to sustain his life force, and serves a functional role in the upkeep of the primary Marvel continuity.

In the character's first appearance, Galactus was depicted as a god-like figure that fed by draining living planets of their energy, and operated without regard to the morality or judgments of mortal beings.

Additional material written by John Byrne, Jim Starlin, and Louise Simonson explored Galactus's role and purpose in the Marvel Universe, and examined the character's actions through themes of genocide, manifest destiny, ethics, and natural/necessary existence.

[7][8][9] In 1966, nearly five years after launching Marvel Comics' flagship superhero title, Fantastic Four, creators Stan Lee and Jack Kirby collaborated on an antagonist designed to break the supervillain mold of the tyrant with god-like stature and power.

While nearly identical to the previous origin, this story featured supplemental material, edits, and deletions by writer Mark Gruenwald, pencillers John Byrne and Ron Wilson and inker Jack Abel.

Rather than traveling into a dying star, the character enters the core of the collapsing universe before the Big Bang; the story was later reprinted as Origin of Galactus #1 (February 1996).

Writer-penciller John Byrne and inker Terry Austin produced "The Last Galactus Story" as a serial in the anthology comic-magazine Epic Illustrated #26–34 (October 1984 – February 1986).

Stan Lee and artist John Buscema also produced the 64-page hardcover graphic novel Silver Surfer: Judgment Day (October 1988), in which Galactus clashes with the demonic entity Mephisto.

She proposed a separate limited series, and at the time was initially doubtful that Marvel would approve what she considered a "radical" idea concerning "why the very existence of the universe depends on the health and well-being of Galactus.

3) #46–49 (October 2001 – January 2002) written by Jeph Loeb and culminate in Galactus' revival, bringing resolution to Simonson's cliffhanger from the Devourer story arc.

Author Andy Lanning said that he and co-writer Dan Abnett were "treating Galactus like a force of nature; an inevitable, planetary catastrophe that there is no reasoning with, no bargaining with and no escaping.

The story features Galactus recounting all the major events that have occurred in Marvel continuity to Franklin Richards as the universe experiences its final moments.

When an unknown cosmic cataclysm gradually kills all other life in his universe, Galan and other survivors leave Taa on a spacecraft and are engulfed in the Big Crunch.

[51] Galactus also rescues the Surfer and Nova II from Mephisto's realm,[52] and aids the cosmic hierarchy in a war against the mad Eternal Thanos, who wields the Infinity Gauntlet.

[56] Galactus then decides, with help from his new herald Red Shift, to only devour the energy of living beings, which brings him into conflict with alien races and Earth's superheroes.

[74] A tear in the fabric of space caused by the Annihilation Wave and other interstellar conflicts allows the extra-universal forces of the Cancerverse (an alternate universe without death) to invade.

[77] After an encounter with the High Evolutionary,[78] Galactus invades Asgard, home of the Norse Gods, seeking an Asgardian artifact to sate his hunger and spare future civilizations.

To avoid a protracted battle, the Silver Surfer offers to remain on Earth to guard the artifact on the condition that Galactus may have it once Asgard eventually passes.

[81] Galactus is then pulled through a hole in space-time to an alternate universe[82] and meets another version of himself: a space-faring mechanical hive mind called Gah Lak Tus.

Galactus locates the hero Anti-Man outside the Multiverse and, after transforming him into a Herald of Life, sends him to recruit the recently disbanded Ultimates to help discover the identity of Eternity's captor, who is later revealed to be the First Firmament, the first iteration of the cosmos.

[89] During the "Infinity Countdown" storyline, the Silver Surfer requests Galactus' aid in defeating Ultron/Hank Pym by consuming the planet Saiph, which is overrun by Ultron drones.

[115] To aid in his search for suitable planets, Galactus frequently appoints an individual as his herald, granting each one in turn a small fraction of the Power Cosmic.

After attempting to use the Ultimate Nullifier to prevent herself from being driven to consume the planet, Galactus replenishes his daughter with cosmic energy and explains her origins to her, leading Gali to realize that she is pregnant.

Having been named a Protector of the Universe by Eon and further empowered with the Quantum Bands, the Keeper possesses sufficient power to constantly supply Galactus with energy, ending his need to consume worlds.

2) features a pocket universe created by Franklin Richards after the events of Onslaught, and includes a version of Galactus with five heralds, each appearing to represent one of the four classical elements according to Greek philosophy: air (Air-Walker), fire (Firelord), water (Plasma) and earth (Terrax).

[167] The MC2 title Last Planet Standing features a future version of Galactus that eventually merges with the Silver Surfer and vows to repair rather than destroy worlds.

To prepare for the arrival, the drones send telepathic broadcasts of "fear", then use envoys (similar to the Silver Surfer), who introduce a flesh-eating virus into planets.

[169] Gah Lak Tus is also involved in the "Chitauri-Kree" War, and temporarily merged with Galactus after a temporal rift sends the latter to the Ultimate Marvel universe.

[83] Mahr Vehl stated the Gah Lak Tus swarm was originally built by the ancient Kree eons ago to eliminate all foes and "purify" the universe, but subsequently escaped their control and evolved into its current form.

[83][170] During "Reckoning War", as punishment for his interference Uatu is forced by his father Ikor to watch the unnamed alternate world where he never interfered to warn the Fantastic Four about Galactus' original attack.