ormed at the dawn of the new millennium, Mastodon would be the newest band to feature Brann Dailor(drums) and Bill Kelliher (vocals/guitar), both formerly of Lethargy and Today Is The Day. Both members brought their influence from Lethargy but less chaotic with vocals that alternate between an almost hardcore scream and a gruff semi-death style. Adding bassist Troy Sanders and guitarist Brent Hinds their Lifesblood EP would arrive in 2001, a concept album loosely based on Herman Melville's novel Moby-Dick. Blood and Thunder featuring Clutch vocalist Neil Fallon was chosen as one of the most important recordings of the decade by National Public Radio in November 2009. The track, along with, Iron Tusk, the fifth track were featured on several video games. Leviathan was followed by Remission (2002) and the 2006 release of Call of the Mastodon, a remastered collection of the band's first nine songs, and a DVD of interviews and concert footage called The Workhorse Chronicles that includes material from the band's early days as a five-piece.
The band recorded a demo in 2000, which featured the band's first lead singer Eric Saner on vocals but he left for personal reasons after only a couple of months.
Blood Mountain (2006) followed along with a tour to support the album along with Tool in Europe and Slayer in Australia and New Zealand.
Crack the Skye (2009) arrived as a standard and deluxe version (which features all songs re-done as instrumental versions as bonus tracks) and entered the Billboard 200 at number 11 a week later. The album was a concept affair about an "out-of-body experience", and the concepts of astral travel, wormholes, Stephen Hawking's theories and the spiritual realm. In order to support the new album, Mastodon toured with Metallica on the latter part of the 2009 European leg of their World Magnetic Tour.
Oblivion EP would arrive in 2009.
Film director Jimmy Hayward contacted the band during their 2009 tour of Europe and told the band how much listening to Blood Mountain had helped his creative process while finishing a screenplay, and offered Mastodon a chance to score the film Jonah Hex. Mastodon used scenes from the film as inspiration during the writing and recording process, with the resulting instrumental soundtrack, Jonah Hex: Revenge Gets Ugly EP, was released on June 29, 2010, through 'Reprise Records'.
In 2010, the band was confirmed as being part of the soundtrack for Namco Bandai Games' 2010 remake of Splatterhouse. The game's protagonist can also be seen wearing a Mastodon T-shirt in certain flashback cut-scenes.
2011 saw Mastodon release their first live DVD/CD entitled Live at the Aragon through 'Reprise'.
The Hunter followed in 2011 with Once More 'Round the Sun (2014) and Emperor of Sand (2017). The EP Cold Dark Place would arrive in 2017.