Mastodon

Mastodon is an American sludge metal/progressive metal band from Atlanta, Georgia, formed in 1999. The band comprises bassist/vocalist Troy Sanders, guitarist/vocalist Brent Hinds, guitarist Bill Kelliher and drummer/vocalist Brann Dailor. They have released six full-length albums to date, expanding their musical borders from early raw sludgy riffs to later psychedelic multi-layered songs, yet maintaining progressive style with unusual time signatures and odd instrumentation.

The band's first demo (referred to simply as the 9 Song Demo) was released in 2000. It is unique in the band's catalogue for featuring the vocals of original vocalist Eric Saner. Other releases followed shortly thereafter, including the 2001 EPs Slick Leg and Lifesblood, which both consisted of re-recorded demo tracks. The band's demo and Slick Leg brought them to the attention of Relapse Records, who would release Lifesblood and their first two albums.