Atlanta progressive metallers MASTODON have written the score to "Jonah Hex", the comic-book Western/horror film starring Josh Brolin in the lead role, with support from John Malkovich, Megan Fox, Will Arnett, Michael Fassbender and Michael Shannon. The movie is based on the DC comic series about a horribly scarred antihero who is "a rough-and-tumble gunslinger and part-time bounty hunter whose adventures always ended in blood."

MASTODON guitarist/vocalist Brent Hinds makes a cameo appearance in the film, which is being directed by former Pixar animator Jimmy Hayward for a June 18, 2010 release.

As MASTODON bassist Troy Sanders told Paste magazine, creating a film score wasn't entirely different from the band's usual songwriting process. "Since day one, we've always written albums thinking the music was the score of a movie," Sanders said. "Then we'll create the lyrics or story line on top of that, as if we're writing the dialogue to match the movie's cinematography."

Regarding how much the band was paid to contribute to the film, Sanders revealed it was "basically nothing."

"[The movie budget] covered our studio fees, but it was a break even deal," he said. "Malkovich, Brolin and Megan Fox all took pay cuts to be a part of this movie — that alone speaks volumes about how much people care about this film."

"I guarantee an incredibly popular misconception will be, 'Oh my god, they're selling out doing a fucking comic-book movie. They probably got a huge paycheck and don't give a shit about integrity,'" Sanders continued. "The fact is the exact opposite. We sacrificed another two weeks away from home to give away an album's worth of material for nothing in return but satisfaction in being a part of something incredible."

MASTODON wrote about an hour's worth of music, all instrumental, including five full songs and many smaller musical themes adapted throughout. Some of the material, Sanders said, will likely be adapted for the London Orchestra for particularly epic scenes. "We wrote variations on themes for each character, different variables for a bunch of riffs: faster, slower, heavier, lighter," Sanders said. "It's the Darth Vader approach."

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