Earth's Mightiest Heroes have new suits in Avengers: Endgame, but why? The latest trailer for Endgame has revealed a lot more about the aftermath of Thanos' snap at the end of Avengers: Infinity War. Nebula, Tony Stark and Carol Danvers are all on Earth to help the team, Hawkeye's going to see a lot more action as Ronin, and Black Widow's hair suggests a pretty sizable time jump. But by far the biggest reveal is the Avengers' new suits.

Seen at the end of the Avengers: Endgame official trailer, the entire team - Captain America, Nebula, Ant-Man, Ronin, War Machine, Iron Man and Black Widow, with Bruce Banner, Thor and Captain Marvel presumably flanking - are wearing new costumes. Each one is personalized to the wearer's size and powers, but all are of the same hard exterior in white, black and red. The Avengers have had connected costumes before - in Avengers: Age of Ultron, Cap sported a small "A" on his shoulder - but nothing compares to this. What's going on?

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The answer goes into long-standing rumors about the plot of Avengers: Endgame that are unlikely to be confirmed overtly until the movie releases, so if you want to go in knowing as little as possible, you may want to look away.

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Still here? OK then: the new costumes in Avengers: Endgame are Quantum Realm suits that will allow the heroes to travel back in time. It's widely accepted that Endgame will see the Avengers travel through time to the events of previous movies in a bid to undo Thanos' snap; set photos have shown Ant-Man and a blonde Tony Stark in the Battle of New York, and all subsequent evidence points in the same dierction. What exactly they're aiming to do is still unclear - the most logical theory is that they're trying to copy the Infinity Stones to do a reversal snap of their own - but we do have a good idea of how they'll go about it.

Avengers Endgame Trailer Team Shot

In the MCU, the most overt manner of time travel is the Time Stone, which was used by Doctor Strange to defeat Dormammu and Thanos to undo the Mind Stone's destruction. Of course, that's currently in the Mad Titan's destroyed Infinity Gauntlet and not at the Avengers' disposal. What they do have access to in the Quantum Realm. Since Ant-Man, it's been established that the laws of time and space break down in the microverse, and in Ant-Man & the Wasp's mid-credits scene - which ended with Scott Lang trapped - he was explicitly warned about "time vortexes".

With Ant-Man turning up at Avengers HQ with the Quantum Tunnel van at the end of Avengers: Endgame's teaser, the team now has access to the realm and, via the recently-escaped Ant-Man, knowledge of how to enter and leave. It's believed that these costumes - called "Advanced Tech Suits" by some tie-in merchandise and looking rather like those worn by Hank Pym in Ant-Man & the Wasp - are intended to protect the Avengers from the negative effects of the Quantum Realm as they go back to movies such as The Avengers and Guardians of the Galaxy. That doesn't explain why Ant-Man himself has a new suit - his regular costume is proven to be suitable for Quantum Realm navigation, but it's surely connected to the nature of the plan.

Related: All The Time Travel Hints In The Avengers: Endgame Trailer

Indeed, while we know what the Avengers' new costumes are for in Endgame, we still know precious little about the bigger plan. And given Marvel's secrecy so far, that will have to wait until the movie releases on April 26.

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