When Galactus threatened the safety of Asgard, both on Earth and in space, Loki finally became a hero by succeeding where Odin failed in Marvel Comics. Before Loki proved his heroism, he seemingly died after being the cause of Asgard’s destruction, forcing them to take refuge on Earth. Loki returned as a child and put villainy behind him, as he went up against the Devourer of Worlds, Galactus, himself.
In The Mighty Thor#1-6 by Matt Fraction and Olivier Coipel, the World Tree Yggdrasil split in two, creating an opening through which cosmic energy was pouring out. Odin sent Thor and Sif to retrieve the Worldheart, otherwise known as the Galactus Seed, from inside Yggdrasil. Odin knew it contained the power to create an entirely new reality. However, the Galactus Seed being pulled into the physical world alerted Galactus to its power, and the Devourer of Worlds sought to take it from Odin. Galactus believed that if he consumed the Worldheart, he would no longer be perpetually hungry and could stop feeding on entire planets. Odin did not want to give Galactus the Seed, no matter how many trillions of lives it could have saved, and so the Asgardians prepared for war.
Related: Thor Killing Galactus Was His Biggest Failure as King
Odin and his army led by Thor met Galactus and the Silver Surfer in space above Earth to vanquish the world killer once and for all. The Asgardians put up a valiant fight, with Odin famously headbutting Galactus in the face during the battle as well, but it was all futile as Galactus is a force of nature that is not easily destroyed. During the battle, Loki remained on Asgard because he wanted to be rid of the Worldheart before Thor got himself killed fending off Galactus. Loki stole the Seed and
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