WARNING: The following contains spoilers for Avengers #51 and Avengers Forever #1, on sale now from Marvel Comics.
While Thor may famously wield Mjolnir, a mythical weapon forged by Odin to channel his powers as the Asgardian God of Thunder, there are plenty of magical hammers scattered throughout the wider Marvel Multiverse. From the hammer of Cul surfacing during the 2011 crossover event Fear Itself to Ultimate Thor's hammer making its way to the main Marvel Universe, there is no shortage of magically charged war hammers ready to be seized by friend or foe. As the Avengers face off against a whole team of supervillains assembled from across the multiverse, a powerful new hammer has arrived in the Marvel Universe that is shaping up to play a pivotal role in determining the fate of Earth's Mightiest Heroes.
One of the worlds devastated by the Multiversal Masters of Evil was Earth-818, which had its prehistoric iteration of the Avengers wiped out by the supervillains. In his dying moments, the Asgardian All-Father of this universe swore that whoever who wielded his version of Mjolnir would "possess the power of All-Vengeance," effectively giving his hammer its own name. Long after the final defeat of Odin, the powerful enchanted hammer is discovered by his world's version of Ant-Man, who is Tony Stark instead of Hank Pym or Scott Lang. As Earth-818 receives some stranger visitors from the main Marvel Universe in Avengers Forever #1 (by Jason Aaron, Aaron Kuder, Cam Smith, Jason Keith, Triona Farrell and VC's Cory Petit), All-Vengeance is destined to have multiple new wielders.
The Tony of Earth-818 is able to lift the hammer, albeit with great difficulty and nearly being crushed in the effort due to being shrunk to his ant size. And while Tony theorizes that All-Vengeance is the same hammer wielded by the All-Father approximately one million years ago on his Earth, the true master of the hammer and its Asgardian-anointed mission is a popular Marvel superhero well-acquainted with the concept of vengeance: Ghost Rider from the main Marvel Universe.
Robbie Reyes and a cybernetic Deathlok had both been transported to Earth-818 shortly before the Avengers fell under siege from the Multiversal Masters of Evil. Robbie's mastery over his powers had been growing noticeably unstable recently but wielding All-Vengeance could finally give him the means to channel his supernatural powers as Ghost Rider. Given that All-Vengeance is empowered by both Mother Storm and the Phoenix Force of Earth-818, wielding the ancient hammer would also make Robbie one of the most powerful Marvel heroes, combining mutant, cosmic and supernatural abilities all through the ancient weapon. With the Multiversal Masters of Evil attacking the main Marvel Universe in Avengers #51 (by Aaron, Juan Frigeri, David Curiel and Petit), Robbie could deliver the long-promised vengeance in full.
The full abilities of the All-Vengeance have yet to be fully unleashed but, given where it draws its powers from, it could rival any other magical hammer in the Marvel Multiverse. Robbie is in need for a way to stabilize his powers as Ghost Rider and the All-Vengeance could not only help with this but give him an upgrade that would make him the ultimate Ghost Rider across the entire multiverse.
That Tony was able to lift the All-Vengeance suggests the hammer's enchantment might not be as restrictive as Mjolnir, and as Marvel's Spirit of Vengeance Ghost Rider and Odin's weapon would be a match made in Hell for anyone who opposes them.