With production rumored to start later this month, Marvel is getting into casting mode for Avengers: Infinity War. Game of Thrones star Peter Dinklage is reportedly in early talks to star in what is said to be a "key role," although no details about the character have been given. Marvel would not comment on the casting, and while the character's identity has not yet been revealed, there is already plenty of speculation about who he may be playing in this Avengers sequel.

Variety reports that production is now expected to start at some point this summer, which contradicts another report from last month that claimed Marvel was gearing up for a January 23, 2017 production start on Avengers: Infinity War. Filming is expected to take place both in Atlanta, Georgia, at Pinewood Atlanta Studios, and in the U.K. It is also believed that both Avengers: Infinity War and Avengers 4 will shoot back-to-back.

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As for Peter Dinklage's character, while no details were given by Variety, shortly after the news broke, Deadpool creator Rob Liefeld took to Twitter to reveal his theory, that Peter Dinklage is playing Pip the Troll, who was originally an antagonist for Adam Warlock. Pip was a Laxidazian alien who became a both physically and psychologically mutated after he became drunk on a mutagenic hallucinogenic ale. He was cast away by his people when he came across Adam Warlock on his travels. Pip was even featured in the Infinity War comics, so Rob Liefeld's theory could certainly be valid, but there is also another theory swirling.

There are also some who speculate that Peter Dinklage may be playing MODOK (Mental/Mobile/Mechanized Organism Designed Only for Killing), which also hasn't been confirmed. It is worth noting, though, that Captain America: Civil War writer Christopher Markus, who is also writing Avengers: Infinity War with his writing partner Stephen McFeely, said in an interview last year that he wants to find a way to bring MODOK into a Marvel movie. While that is far from any confirmation that Peter Dinklage is playing MODOK, it's certainly an interesting angle to consider, until we have full confirmation from the studio.

This casting news comes just a few days after another rumor surfaced that Liv Tyler may be reprising her Betty Ross character from the Phase One movie The Incredible Hulk, but that hasn't been confirmed either. Anthony Russo and Joe Russo are directing from a script by Christopher Markus and Stephen McFeely, with Marvel Studios president Kevin Feige producing. There has been talk that the entire Marvel Cinematic Universe will come together to fight Thanos (Josh Brolin), but the studio has yet to confirm a cast list quite yet for Avengers: Infinity War. While best known for his role as Tyrion Lannister in HBO's Game of Thrones, Peter Dinklage is no stranger to the superhero realm, playing Bolivar Trask in 20th Century Fox's 2014 movie X-Men: Days of Future Past. While we wait for more on Avengers: Infinity War, take a look at Rob Liefeld's tweet below.