WARNING: The following contains spoilers for Avengers #39 by Jason Aaron, Dale Keown, Scott Hanna, Jason Keith and VC's Cory Petit, on sale now.

In 2017, the Marvel Legacy relaunch kicked off by revealing that there was another team of Avengers prior to the one first formed by Iron Man, Thor, the Hulk, Wasp, Ant-Man and Captain America. Indeed, a prehistoric team of Avengers was assembled at the dawn of time itself in the year 1,000,000 BC. This version of Earth's Mightiest Heroes was comprised of the King of Asgard, Odin, the first mutant host of the Phoenix Force, the powerful magician Agamotto, the Starband and the first wielders of the Black Panther, Iron Fist and Ghost Rider mantles.

Since then, we've learned more and more about these Avengers and the threats they faced in their time, such as a Celestial and a young Thanos. Now, in Avengers #39, we finally learn how the team was originally brought together and who it was that first assembled them.

As it turns out, it's someone fans might not have expected: the Phoenix.

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When the Avengers of the year 1,000,000 BC were first introduced, it was easy to assume that Odin was the leader of the team. After all, he is a character familiar to Marvel fans and, as the King of Asgard, he is a natural leader. What's more, he was armed with Mjolnir, a recognizable weapon that also indicated a certain amount of leadership. That is why it comes as such a surprise to learn, in Avengers #39, that Odin is not actually the one who assembled the world's first superheroes.

Avengers #39 features the origin story of the redheaded girl who would become one of the world's very first mutants. When she was born, she was left to die in the Burnt Place because she was deemed different. But she didn't die -- instead, she was rescued by wolves, and she grew up to become part of their pack.

Years later, the little girl returns to the Burnt Place, and it's there that she comes across the Highwalker, a telepathic mutant who is meant to be a reflection of the X-Men's Professor X. The telepath has assembled a tribe of mutants in a safe place where he can teach them to use their special abilities. The girl goes with him, but it isn't long before humans attack them.

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When the dust settles, the mutants and the cavemen are dead and the redheaded girl is the only one who is left alive. With her full powers unlocked, the Phoenix Force bonds with her, and although she intends to destroy the world, she spares it when a wolf approaches her, reminding her that she was once saved. This inspires the Phoenix to become a force for good, to protect the world and others from those who would do them harm.

Years later, the Phoenix smashes through the gates of Asgard and finds Odin. Now in full control of her powers and flanked by an army of wolves, the Phoenix introduces herself to the All-Father and informs him that she is putting a team together.

She essentially acts as the Marvel Cinematic Universe's Nick Fury, who famously appeared in Iron Man to talk to Tony Stark about the Avengers Initiative. But here, it's the Phoenix who finds her first recruit in Odin. Of course, we know that Odin will accept. Better yet, five more superheroes will join their cause. Hopefully, further issues of the series will show how the Phoenix, with Odin's help, recruited the rest of Earth's first Mightiest Heroes.

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