Metalcore continued to rage in the mid-2000s, and Manntis fueled the fire. Active since 2000 in and around southern California, Manntis didn't gain a foothold nationally until 2004 and the band's participation in MTV's Battle for Ozzfest, a reality contest that pitted up-and-coming metal hopefuls against each other in competition for a record deal and Ozzfest tour spot. Manntis didn't win the competition, but it still gave them a chance to tour the nation. By April 2005, vocalist Jake Sirokman, guitarists Adair Cobley and Jeremy Swanson, bassist Clint Gregory, and drummer James Sanders had been signed by Century Media; Sleep in Your Grave, Manntis' roaring debut, appeared the following June. ~ Johnny Loftus, All Music Guide