Marvel's WHAT IF? returns with a series of cosmos-shattering tales in which surprising new heralds serve the Devourer of Worlds! A series of shocking stories explore the possibilities of some of Earth's greatest heroes pledging themselves to Galactus! When the World-Eater enlists the Incredible Hulk as his herald, what will turn out to be the bigger mistake: trying to direct the fury of the Green Goliath or giving the great mind of Bruce Banner a cosmic problem to solve? Gambit is the most charismatic and capable thief on Earth - which is exactly how he grabs the attention of the Devourer of Worlds! With the Power Cosmic flowing through his veins, Gambit is unstoppable - but is he clever enough to steal the unstealable? When Khonshu and Galactus clash, Moon Knight is caught in the middle - but when Marc Spector takes his turn as herald, his alters manifest in startling new ways! A young Rogue uses her mutant power to absorb the Power Cosmic of the Silver Surfer, changing the entire course of her storied history! And after coming to the aid of a wounded herald of Galactus, Spider-Gwen is empowered in the Devourer's service! Collecting WHAT IF... ? GALACTUS TRANSFORMED HULK?, WHAT IF... ? GALACTUS TRANSFORMED GAMBIT?, WHAT IF... ? GALACTUS TRANSFORMED MOON KNIGHT?, WHAT IF... ? GALACTUS TRANSFORMED ROGUE? and WHAT IF... ? GALACTUS TRANSFORMED SPIDER-GWEN?