The Marvel Cinematic Universe kicked off at the end of Iron Man in 2008 with a post-credits scene that featured Nick Fury (Samuel L. Jackson) approaching Tony Stark (Robert Downey Jr) about something called the Avengers Initiative. The first phase of Marvel Studios' MCU came to a conclusion in The Avengers, which featured Iron Man, Captain America, Black Widow, Hulk, Hawkeye and Thor teaming up to defeat an alien invasion - but it additionally introduced Thanos (Josh Brolin). Throughout Phases 1 and 2 of the MCU, Marvel has set up for an epic battle between Earth's Mightiest Heroes and Thanos that will kick off in Avengers: Infinity War.

But, since Thanos will prove to be a greater enemy than The Avengers have ever faced before, they'll be calling in some reinforcements. Enter: the Guardians of the Galaxy. Introduced in James Gunn's 2014 MCU entry, the ragtag team of heroes became fan-favorites and they're set to first meet Marvel's Earth heroes in Avengers: Infinity War. Now, new concept art for the upcoming film offers a first look at a Guardian and an Avenger teaming up.

Marvel debuted a behind-the-scenes featurette from the first day of filming Avengers: Infinity War that includes a shot of concept art depicting Guardians of the Galaxy's Rocket Raccoon battling alongside the God of Thunder himself, Thor. While Rocket (voiced by Bradley Cooper) appears to be wielding the guns that first appeared with him in Guardians, Thor (Chris Hemsworth) isn't holding Mjolnir - though it's unclear what weapon he is using. Take a look:

Avengers Infinity War Rocket Raccoon Thor Concept Art

The Avengers: Infinity War video additionally features new concept art of Thanos, interviews with Marvel Studios head Kevin Feige as well as co-directors Anthony and Joe Russo, and plenty of promises that the third Avengers film will be a must-see event. Plus, while the video doesn't reveal too much about how the characters will interact on-screen, it does feature Downey Jr., Tom Holland, and Chris Pratt talking about their roles as Iron Man, Spider-Man, and Star-Lord, respectively.

Interestingly enough, this particular bit of Avengers: Infinity War concept art features two character that are set to appear in MCU films later this year - prior to their appearance in Avengers 3 when it hits theaters next year. Rocket will appear in Gunn's galactic followup to his 2014 entry, Guardians of the Galaxy Vol. 2, while the God of Thunder will headline his third solo film in Taika Waititi's Thor: Ragnarok. Both movies will offer fans a chance to see Rocket - along with his pal, Baby Groot - and Thor in action in 2017.

Still, fans are no doubt looking forward to the team-up of the Avengers and the Guardians given how well audiences have responded to both teams. Thankfully, with Avengers: Infinity War moving ahead with production in order to meet the film's 2018 release date, fans won't have to wait too long before all their favorite Marvel heroes appear on the big screen together.

Next: Infinity Stones In Marvel Movies Explained

Source: Marvel

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