For the past week Robert Downey Jr. has teased the possibility of an Iron Man 4, also claiming that he is in negotiations for 'other' Marvel movies. Last night news broke that Tony Stark will actually be appearing in Captain America 3 in a substantial role, and that it will kick off an event fans have been clamoring for: Marvel's Civil War. Now comes news that Captain America 3 directors Anthony Russo and Joe Russo may actually take on The Avengers 3 and The Avengers 4, which will likely have completely new character line-ups from the first two movies.

Marvel's Civil War is a massive crossover for Marvel's biggest and brightest heroes, with Iron Man and Captain America at the center of it. The story finds Robert Downey Jr.'s Iron Man/Tony Stark going against Chris Evans' Captain America/Steve Rogers, both with opposing views over the Superhero Registration Act, which forces anyone with super-human abilities to register themselves with the U.S. government, and agree to serve as part of a new police force. In the comics, these events led to the eventual death of Steve Rogers, with the Winter Soldier stepping in to take his place.

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Marvel's Civil War will begin on May 6, 2016, when Captain America 3 hits theaters. And many now speculate that this is why Warner Bros. and DC eventually moved Batman v Superman: Dawn of Justice. A brawl between Iron Man and Captain America stands to equal or obliterate whatever tussle Bruce Wayne and Kal-El have planned, especially in a movie that promises quite a few Marvel superhero cameos.

Last night, Marvel announced that it is relaunching the Civil War comic book series:

According to a new report at Badass Digest, Captain America 3 may be the biggest movie Marvel has ever attempted, and it will tear at the very fabric of the Marvel Cinematic Universe in the same way that Captain America: The Winter Soldier has, with the dissolution of S.H.I.E.L.D. Their claim is that Joe Russo and Anthony Russo are coming back to continue the Civil War storyline in The Avengers 3 and The Avengers 4, sequels that will take us to the end of this decade.

Insiders say that both directors are in talks at this very moment to return for both sequels, and that's why we may not have titles for all the previously announced release dates Marvel has already released. Staking claim was needed to map out this extensive plan, which is moving forward like a grand army, and the Studio needs all its pieces in the right place before it can fully divulge what is happening with the public.

Both Variety and Badass Digest suggest that Robert Downey Jr. is going to return for The Avengers 4, but that has never been confirmed by the actor or the studio. And it may not happen, as more characters are introduced in the MCU.

It's also being suggested that Thanos is what will bring all of the superheroes back together once the dust has settled on Marvel's Civil War. It will also allow for the Guardians of the Galaxy to enter the fold. In what movie, and what fashion this all plays out is anybody's guess at the moment.