Warning: Contains spoilers for Hulk vs Thor: Banner of War Alpha #1
After Thor had to destroy Mjolnir to get rid of the soul of the evil Mangog infesting it, the All-Father of Asgard had his hammer reforged, only to find out that the spirit of the deceased Odin now resides inside the weapon. While Thor may not be happy about his father's persisting influence in his life, this new upgrade makes Mjolnir and the God of Thunder more powerful than they have ever been.
Mjolnir was originally forged by the dwarven smiths of Nidavellir under the orders of Odin when the King of Asgard needed a way to trap the God Tempest, a powerful and unruly primordial being he had bested in battle. While proving to be a mighty weapon, the God Tempest's lingering spirit made Mjolnir a whimsical tool, so the One-Eyed God decided to leave it for his son Thor to inherit when he proved to be worthy. Recently, the spirit of the deceased Mangog, one of Asgard's most relentless enemies, found a way to bond with the God Tempest inside Mjolnir, creating a vengeful and almost unstoppable creature that called herself the God of Hammers and went so far as to kill Odin. To defeat her, Thor had to destroy Mjolnir. The spirit of his father, finding Valhalla to be razed and destroyed by an unknown enemy, has now come back and taken residence inside the weapon.
Related: Thor Comics Confirm The Best Way To Bring Odin Back To The MCU
When Thor learns from his trusted ravens the location of the fugitive Hulk, sought by the Avengers for causing a massacre in El Paso, he immediately goes to intercept the Green Goliath. Itching for a fight to forget about the many unpleasant events that followed his ascension to the throne of Asgard, Thor wastes no time in attacking
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