The band have 3 albums to date; Leviathan (2004), Blood Mountain (2006) and Crack the Skye (2009), and bassist Troy Sanders told Paste Magazine that the music of the score was a departure from the band's metal sound.

Mastodon

“Some of it was heavy, some of it was very moody. A lot of it was spacey, Melvins B-sides, Pink Floyd-like, surreal outer space, like Neil Young’s Dead Man. Swirling, nausea music.”

However, the stretch from writing full-album material to scoring a movie was not too great for the band, as Sanders said :

“Since day one, we’ve always written albums thinking the music was the score of a movie. 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.”

Sanders said that Mastodon took on the movie score after a phone call from director Jimmy Hayward, who had been listening to the band whilst shooting the movie, asking them to get involved.

“As opposed to labels profiteering the situation, saying they’d give a band $500,000 to use some song, he called us out of the blue as a fan, It was the most beautiful, authentic way to collaborate.”

“[The movie budget] covered our studio fees, but it was a break even deal. 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.

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.”

The original article is here.