Metalcore, an originally American hybrid of thrash metal and hardcore punk, emerged as a commercial force in the mid-2000s. It is rooted in the crossover thrash style developed two decades earlier by bands such as Suicidal Tendencies, Dirty Rotten Imbeciles, and Stormtroopers of Death. Through the 1990s, metalcore was mostly an underground phenomenon. By 2004, melodic metalcoreŚinfluenced as well by melodic death metalŚwas popular enough that Killswitch Engage's The End of Heartache and Shadows Fall's The War Within debuted at numbers 21 and 20, respectively, on the Billboard album chart. Bullet for My Valentine, from Wales, broke into the top 5 in both the U.S. and British charts with Scream Aim Fire (2008). In recent years, metalcore bands have received prominent slots at Ozzfest and the Download Festival. Lamb of God, with a related blend of metal styles, hit the Billboard top 10 in 2006 with Sacrament. The success of these bands and others such as Trivium, which has released both metalcore and straight-ahead thrash albums, and Mastodon, which plays in a progressive/sludge style, has inspired claims of a metal revival in the United States, dubbed by some critics the "New Wave of American Heavy Metal."
Children of Bodom, performing at the 2007 Masters of Rock festival
The term "retro-metal" has been applied to such bands as England's The Darkness and Australia's Wolfmother. The Darkness's Permission to Land (2003), described as an "eerily realistic simulation of '80s metal and '70s glam," topped the UK charts, going quintuple platinum. One Way Ticket to Hell... and Back (2005) reached number 11. Wolfmother's self-titled 2005 debut album had "Deep Purple-ish organs," "Jimmy Page-worthy chordal riffing," and lead singer Andrew Stockdale howling "notes that Robert Plant can't reach anymore." "Woman," a track from the album, won for Best Hard Rock Performance at the 2007 Grammy Awards. Slayer's "Eyes of the Insane" won for Best Metal Performance in 2007; their "Final Six" won the same award in 2008.
In continental Europe, especially Germany and Scandinavia, metal continues to be broadly popular. Well-established British acts such as Judas Priest and Iron Maiden continue to have chart success on the continent, as do a range of local groups. In Germany, Western Europe's largest music market, several continental metal bands placed multiple albums in the top 20 of the charts between 2003 and 2008, including Finnish melodic death metal band Children of Bodom, Norwegian symphonic extreme metal act Dimmu Borgir, and two power metal groups, Germany's Blind Guardian and Sweden's HammerFall. The Swedish melodic death metal act In Flames took both Come Clarity (2006) and A Sense of Purpose (2008) to number 6 in Germany; each album topped the Swedish charts.