Mastodon was an American band that created complex song structures and included oddly-distorted guitars. Much of the band's lyrical content concerned mythical stories and creatures. Mastodon's "Blood Mountain" was considered among the best albums of 2006 by Pitchfork and Pop Matters.
Known for playing death metal music with random acoustic passages, Opeth was a Swedish heavy metal group that first started playing in the 1990s. Opeth released "Ghost Reveries" and "Watershed" between 2005 and 2008. "Watershed" received a nine out of 10 review from "All Music Guide."
Baroness was an American band known for mixing metal with a sludgy, southern classic rock sound. Baroness also sometimes blended Eastern influences into their songs through specialized guitar effects. Their debut, "Red Album" was released in 2007. "Metal Review" gave "Red Album" a score of 8.9 out of 10.
The Dillinger Escape Plan from New Jersey crossed acrobatic percussion, deep screams and growls and very fast guitar parts. The band released its third album, "Ire Works" in 2007. "Ire Works" got an eight out of 10 score from Pitchfork. The Dillinger Escape Plan remained active as of 2011. Its recordings included a cover of Public Enemy's "Fight the Power."
Clutch mixed vocals and sharp guitar riffs with a southern rock style. The American band released two full length albums, "Robot Hive/Exodus" and "From Beale Street to Oblivion," between 2005 and 2008. "Robot Hive/Exodus" was given an eight out of ten score by Pop Matters.
System of a Down had an unusual background. They were from California, but made up of Armenian musicians. They got on the radio with songs like "Spiders" and "Chop Suey!" in the early part of the decade. The band released two critically albums, "Mezmerize" and "Hypnotize" in 2005. Shortly afterwards it started a hiatus that didn't end until 2011.
Russian Circles was an instrumental band that often blended high, chiming guitar parts with building percussion before going harder and heavier with severely distorted guitars. The discs "Enter" and "Station" came out between 2005 and 2008. "Alternative Press" gave "Station" an eight out of 10 score.
Metallica was a huge hit in the metal world before 2005, and reinforced that fame with "Death Magnetic" in 2008. Full of barking vocals and traditional guitar lines, "Death Magnetic" got an 8.6 out of 10 score from "Paste" magazine. It sold just under 500,000 copies in its first three days of release, which made it the fifth Metallica album to reach No. 1 on the "Billboard" charts.
Meshuggah was a Swedish metal band that used eight-string guitars to add more complex song structures and a deeper sound than bands using six-strings. Meshuggah released "Catch 33," "Selfcaged" and "Obzen" between 2005 and 2008. The Onion A.V. Club gave "Obzen" a perfect rating.
The Japanese band Boris released three full length albums between 2006 and 2008. Boris crossed the guitar riffs of metal music with experimental tendencies that bordered on slow-drone music. The Boris album "Rainbow" got an A-minus rating from "Stylus" magazine.