WARNING: The following article contains spoilers for Doctor Strange #15, from Mark Waid, Barry Kitson, Scott Koblish, Brian Reber and VC's Cory Petit, on sale now.

The latest arc in Doctor Strange is proving to be one of the title's most important stories, as Stephen Strange finds himself battling a Galactus who's been levelling up in order to carry out his duties as the Devourer of Worlds. Strange brokered a deal recently with the villain to feed on abandoned planets found only in the mystical realm, but that's since backfired, with Galactus getting co-opted by one of Sorcerer Supreme's biggest enemies: Dormammu.

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However, in Doctor Strange #15, Galactus decides to make his power-up a bit more permanent and become even stronger than what Dormammu initially envisioned. The Devourer of Worlds ends up killing Dormammu and consuming his very essence, setting up the "Herald Supreme" storyline for a riveting finish.

When Dormammu imprisons and taunts Strange, he reveals that, while Galactus thinks the lord from the dark dimension is his herald, it's really the other way around. Dormammu sees Galactus as his lackey. However, it's this arrogance Strange decides to use as a weapon. He knows the clock is ticking, and it's just a matter of time before Galactus starts exerting his influence outside the mystical realm and going after planets like Earth, and empires like those of the Shi'ar and Skrull

Things are already going haywire as the very concept of science and magic merge into one, creating a new energy that's tethered to the Devourer, pulling him to various worlds. At this point, Strange coaxes Dormammu into confronting Galactus to let him know who's the boss. Galactus is undaunted and, as he's already found a way of appropriating this dark energy, he's no one's puppet. Their argument ends with Galactus weakening Dormammu and consuming him, feeding off his energy and making his new transformation permanent.

Strange confirms Dormammu is dead, as he can't sense his presence anymore. Strange attempts to reason with Galactus, but it doesn't work. Despite Dormammu being gone, Galactus is still aiming to fulfill Dormammu's original mission: seek, feed and destroy. Strange can't help but panic because of Galactus' new power-up, which represents and even greater increase than when he became the Lifebringer. With Galactus now the ultimate destroyed, Strange is left with no choice but to bring in the big guns, as they have a "god to topple."

Scrambling, Strange rescues Clea and Umar (Dormammu's sibling) from Mephisto, who put Dormammu's plan into his head, deciding he has to assemble a bigger squad to take the villain down. It's Strange's last resort, because both Eternity and the Living Tribunal won't intervene despite Strange's pleas. They see this as the cosmos running its natural course and believe Galactus might actually be a warped form of balance and evolution.

With that in mind, Strange's new army includes Black Bolt, the Hulk, Magik, Scarlet Witch and a plethora of heroes (and some villains too) as part of a desperate alliance. Strange lays down the law and reminds everyone, including the Silver Surfer, this is the most powerful iteration of Galactus he's even encountered. Given just how powerful Galactus now is, this is one fight Strange won't be able to bargain his way out of.

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Doctor Strange #16 goes on sale July 1.