Marvel stars Robert Downey Jr., Chris Evans and Mark Ruffalo engage in mustache war on social media. Playing three of the founding heroes of the MCU - Tony Stark/Iron Man, Steve Rogers/Captain America and Bruce Banner/Hulk respectively, the actors have been in the franchise since Phase 1. Next month, they are set to star in Avengers: Endgame which will be the culmination of everything that has transpired in the universe for the last decade.

Directed by Joe and Anthony Russo, Endgame will be the direct sequel to last year's Avengers: Infinity War, which was the coming out party the intergalactic villain Thanos (Josh Brolin). The movie didn't end well for the heroes, as they were handed their first real defeat at the hands of the Mad Titan, who gathered all six Infinity Stones and executed The Decimation. This resulted in half of life in the universe disintegrating into dust, including some of the MCU heroes. With this, the remaining Avengers and their allies are expected to do everything in their power to restore peace and order in the galaxy and have Thanos pay for his sins. The film's press tour is expected to begin in a couple of weeks and the actors' recent social media banter is already exciting a lot of fans for it.

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This debacle first started when Downey posted a collated image of the three of them having the '70s-style facial hair that had renaissance recently on his official Twitter account. The photo featured the actor during the 2008 Iron Man press conference in Tokyo, Evans at the launch of the Broadway play Lobby Hero last year, and an old headshot of Ruffalo, taken by photographer Jim Wright. In the caption, he asked the public "who wore it best?" While fans go crazy in the comment section to vote on their personal picks, Ruffalo chimed in on the conversation with a collage of mostly his face sporting different mustaches over the years. See the tweets below:

Mustaches and facial hair in general had been a hot topic in the comic book movie realm in the last couple of years. Captain America's full-bearded look in Infinity War revealed in the movie's first trailer was the talk of the town and many were actually hoping that he would've kept it for Endgame. Over at the DC side of things, it's quite a touchy subject to discuss with Henry Cavill's mustache controversy. The actor who plays Superman on the big screen was working on Mission: Impossible - Fallout when he was called back for extensive Justice League reshoots. But since he was unable to shave his facial hair, Warner Bros. had to digitally remove it during post-production, which didn't have the best result.

Back to Marvel - regardless of who won the accolade for best mustache in the Downey's Twitter poll, this back-and-forth is effectively marketing Avengers: Endgame without even directly mentioning the film. The MCU actors have regularly engaged with each other online to the delight of their fans. Just recently Evans and Downey had a back-and-forth with a subtle reference to their characters' conflict in Captain America: Civil War. This kind of fun dynamic even off-camera makes them much charming and easier to root for, and the public is definitely looking forward to more of these when they begin promoting the film next month.

More: Avengers 4 Directors Manipulated Trailer Footage to Keep Fans Guessing

Source: Robert Downey Jr., Mark Ruffalo

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