Warning! Spoilers for Fantastic Four #45 by Marvel Comics
At the conclusion of the Reckoning War, Galactus has been reborn into something new. In Fantastic Four #45 by Marvel Comics, the Devourer of Worlds transforms into his old form, splitting up from the Destroyer. However, instead of returning to hunger on planets, Galactus has a new purpose in the universe, which takes him on an all-new mission that could redefine the cosmic being in the future.
In the Reckoning War event at Marvel Comics, Galactus transformed into an even more terrifying form after Silver Surfer bonded his former master with the Asgardian Destroyer armor. With the Reckoning on the verge of entering the Apex of All Reality and potentially causing irreversible harm to the Multiverse, Silver Surfer and Earth's Mightiest Heroes realized Galactus was one of their only chances at stopping the destructive aliens. Luring him with the Ultimate Nullifier, the fiery new form of the cosmic juggernaut reached the Apex right as Reed Richards used the weapon to kill the Reckoning's leader. In the wake of the incredible power going off, Galactus has been reborn, getting a new beginning of sorts in the wake of the near-death of the universe.
In Fantastic Four #45 by Dan Slott, Farid Karami, Jesus Aburtov, and VC's Joe Caramagna from Marvel Comics, the greatest cosmic forces in the Marvel Universe evacuate the Watcher's world. In the aftermath of Reed Richards using the Ultimate Nullifier, the hero is revealed to be alive, as firing the deadly weapon drew the Watcher energy out of him. After the heroes get thanked for saving the Multiverse and Uatu gains more powers after absorbing the knowledge of the Apex, he undoes the damage caused due to the Watcher's negligence, including fixing the barrens of the universe. Then, in another massive change to the cosmos, Galactus is reborn as an all-new being with an all-new hunger.
While the cosmic forces in the universe stress time will tell if Galactus has changed, when Silver Surfer asks him if he hungers, he responds, "yes." But, it's not planets he seeks to destroy; instead, the former Devourer of Worlds requires knowledge. So, the Silver Surfer agrees to guide Galactus' new mission, but under his : not as a herald, but as his companion. Ultimately, Galactus and Silver Surfer head off together to explore the universe.
Galactus being reborn doesn't mean that he won't eventually return to being the Devourer of Worlds. After all, that role is important in the name of cosmic balance in the Marvel Universe. However, the new Galactus doesn't want to feed his hunger, but instead, his knowledge. By the Reckoning War's end, Galactus is reborn into something new that readers will later find out exactly what his drastically changed role means.
