Newly released concept art for 2008's Iron Man shows an alternate version of Tony Stark's Mark III armor.

On Instagram, concept artist Phil Saunders -- who is known for his work on such Marvel Cinematic Universe projects as 2012's The Avengers, 2016's Captain America: Civil War and 2021's WandaVision -- shared his first sketch for Tony's Mark III armor in Iron Man. Dated June 6, 2006, the drawing shows Saunders' attempt to "capture the vibe of the original red and gold suit from the comics, and give a him a thick-armored 'bruiser' look." While there are numerous similarities to the final version of the Mark III armor in Iron Man, this version of the suit is noticeably bulkier and less sleek.

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Directed by Jon Favreau from a screenplay by Mark Fergus, Hawk Ostby, Art Marcum and Matt Holloway, Iron Man was the first film in the MCU and explored the origins of the titular hero. The project, which starred Robert Downey Jr. as Stark, proved a success at the box office and earned more than $585 million against a budget of $140 million. Iron Man was also a hit with critics and earned a 94 percent on Rotten Tomatoes.

Following the release of Iron Man, Downey Jr. returned for two direct sequels and several other MCU films. His most recent appearance was in 2019's Avengers: Endgame. However, following Iron Man's death at the end of that film, Downey Jr. is not expected to reprise the role any time soon. Still, Iron Man did recently appear in the MCU, with actor Mick Wingert voicing the character in last year's animated What If...? series on Disney+.

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Created by Stan Lee, Larry Lieber, Don Heck and Jack Kirby, Iron Man first appeared in 1962's Tales of Suspense #39. A genius inventor and the owner of Stark Industries, Iron Man has served as a key member of the Avengers since the team's founding thanks to his powerful armored suits. In 2020, Marvel Comics launched a new series starring the Armored Avenger. Written by Christopher Cantwell and illustrated by such artists as Cafu and Angel Unzueta, new issues of Iron Man release monthly.

All three Iron Man films are available to stream now on Disney+ or own on home media.

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Source: Instagram