The Heralds of Galactus are fictional characters appearing in publications published by Marvel Comics. The Herald concept was introduced in Fantastic Four #48 (March 1966) - with the character the Silver Surfer - by Stan Lee and Jack Kirby.
The Heralds existing in the main continuity of the Marvel Universe include the Fallen One, retroactively revealed to be the first Herald in Thanos #11 (Aug. 2004); the Silver Surfer in Fantastic Four #48 (March 1966); Gabriel the Air-Walker in Fantastic Four #120 (March 1972) (revealed to be an android copy of the original in Thor #305 - 306 (March - April 1981); Firelord; the Destroyer (a temporary substitute); Terrax the Tamer; Nova (Frankie Raye); Morg the Executioner; Red Shift; Johnny Storm and Stardust.
The cosmic entity Galactus maintains his existence by devouring planets that have the potential for supporting life, and as such utilizes a Herald to scour the universe in search of suitable worlds. Upon pinpointing the requisite planetary body, the Herald signals Galactus, resulting in his arrival on the world's surface followed by the deployment of the Elemental Converter — a colossal machine capable of draining all life energy from the planet within minutes. If the world in question supports a sentient civilization, the Herald will often be forced into battle with inhabitants who attempt to drive Galactus away.
Prior to the revelation that the prototype Herald the Fallen One exists, Norrin Radd was considered to be Galactus' first Herald, offering his services in exchange for sparing his planet, Zenn-La. Galactus accepts, transforming Radd into the Silver Surfer.
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