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?