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Slayer is an American thrash metal band from Huntington Park, California. The band was formed in 1981 by vocalist/bassist Tom Araya and guitarists Kerry King and Jeff Hanneman. Slayer's fast and aggressive musical style made them one of the founding "big four" bands of thrash metal, alongside Metallica, Megadeth and Anthrax. Slayer's current lineup comprises King, Araya, drummer Paul Bostaph and guitarist Gary Holt.

Following the success of Hell Awaits, Slayer was offered a recording contract with Russell Simmons and Rick Rubin's newly founded Def Jam Records, a largely hip hop-based label. The band accepted and with an experienced producer and major label recording budget, the band underwent a sonic makeover for their third album Reign in Blood resulting in shorter, faster songs with clearer production. Gone were the complex arrangements and long songs featured on Hell Awaits, ditched in favor of stripped down, hardcore punk influenced song structures.  Def Jam's distributor, Columbia Records, refused to release the album due to the song "Angel of Death" which detailed Holocaust concentration camps and the human experiments conducted by Nazi physician Josef Mengele. The album was distributed by Geffen Records on October 7, 1986. However, due to the controversy, Reign in Blood did not appear on Geffen Records' release schedule. Although the album received virtually no radio airplay, it became the band's first to enter the Billboard 200, debuting at number 94, and the band's first album certified gold in the United States.  In October 1986, Slayer embarked on the Reign in Pain world tour, with Overkill in the US, and Malice in Europe. The band was added as the opening act on W.A.S.P.'s US tour, but just one month in, drummer Lombardo left the band: "I wasn't making any money. I figured if we were gonna be doing this professionally, on a major label, I wanted my rent and utilities paid." To continue with the tour, Slayer enlisted Tony Scaglione of Whiplash. However, Lombardo was convinced by his wife to return in 1987. At the insistence of Rubin, Slayer recorded a cover version of Iron Butterfly's "In-A-Gadda-Da-Vida" for the film Less Than Zero. Although the band was not happy with the final product, Hanneman deeming it "a poor representation of Slayer" and King labeling it "a hunk of shit," it was one of their first songs to garner radio airplay.

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it became the band's first to enter the Billboard 200, debuting at number 94, and the band's first album certified gold in the United States.