Warning: SPOILERS for FCBD: Avengers

Tony Stark has traveled back to the earliest days of planet Earth’s heroes… and he’s not alone. The prehistoric version of Marvel’s Universe is filled with threats even an Iron Man can’t match, which means it’s a good thing he’s run right into the Avengers from 1,000,000 BC.

That’s quite a twist, even for the Avenger who makes the impossible possible on a daily basis. But the real meaning is being kept under wraps for now, with the Free Comic Book Day issue of Avengers promising that at some time, in some place, the heroes put an end to the current War of the Realms. That’s when Tony travels back in time one million years, with no way of returning home. But he’ll have one heck of a story to tell when he does.

The issue begins by tossing Tony into an unknown world, only aware that he’s not in Kansas anymore. Not to mention the fact that he is staring down some saber-toothed cats upon his arrival (why doesn’t he blast them with his repulsors? We don’t know, maybe Iron Man’s a cat lover… or doesn’t want to cause a ripple affect across time. Even odds). Given the frozen terrain and the less than friendly welcome party, Iron Man deduces that he’s been time displaced as a result of tampering with a “doohickey” (technical term) that was dug following the larger War of the Realms event. Just as Iron Man is about to be torn open like a can of tuna, Mjolnir comes flying in save him.

Naively, Iron Man assumes that Thor has come to the rescue. But the reveal leaves Iron Man (and the reader) with more questions than before… since the god wielding the hammer isn’t Thor, but his father Odin. A young Odin, surrounded by his team of prehistoric Marvel heroes–the 1,000,000 BC Avengers!

To demonstrate just how much time we’re talking, this version of Odin doesn’t even know the name ‘Thor’ when Tony brings him up. At this point in the Marvel Universe, Thor is nothing but a twinkle in Odin’s eye (both of them, actually). Not to mention how many years Odin still has before he parts way with the Phoenix-Force-possessed woman he’s currently in love with, and eventually finds his future Queen Freyja, All-Mother of Asgard. These Avengers of 1,000,000 BC have been teased since Marvel Legacy #1, where fans saw them in action against a diseased Celestial that had fallen to Earth. The team seemed at the time to be part of writer Jason Aaron’s attempt to weave Celestials into the fabric of Marvel’s Earth–including moving Avengers HQ to the dead body of a Celestial at the north pole–but is obviously far more important.

The team (seen above) is comprised of a Mjolnir wielding Odin, untold eons before he passes the weapon to Thor. A cave woman who is the first to be possessed by the Phoenix Force (after Aaron revealed Wolverine and Thor will be its final hosts). Add in the first and undeniably the coolest version of Ghost Rider who rides a flaming mammoth, a caveman with the mark of Starbrand (of a Hulk-ish nature), the very first female Iron Fist, Black Panther, and Agamotto the original Sorcerer Supreme.

Iron Man has some explaining to do, or he might have to face off against Odin and these Mightiest Heroes of Midgard. But if anyone in Marvel’s prehistoric world knows how to travel forward through time… you’re looking at them.

Free Comic Book Day 2019: Avengers is available now from your local comic book store.

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