Professional ratings
Review scores
Source	Rating
AllMusic
Collector's Guide to Heavy Metal	7/10
Kerrang!	unfavorable
Metal Forces	9/10
Rock Hard	9/10
The Rolling Stone Album Guide
Sputnikmusic	4/5

Show No Mercy is the debut studio album by American thrash metal band Slayer, released in December 1983 through Metal Blade Records. Brian Slagel signed the band to Metal Blade after watching the band perform the song "Phantom of the Opera" by Iron Maiden. The band self-financed their debut album, combining the savings of vocalist Tom Araya, who was employed as a respiratory therapist, and money borrowed from guitarist Kerry King's father.

Touring extensively promoting the album, the band brought close friends and family members along the trip, who helped backstage with lighting and sound. Although criticized for poor production quality, it became Metal Blade Records' highest selling release, also producing the songs "Die by the Sword", "The Antichrist" and "Black Magic", which are played at Slayer's live shows regularly.

Slayer was the opening act for Bitch at the Woodstock Club in Los Angeles, performing eight songs—six being covers. This concert is available to watch on YouTube. While performing an Iron Maiden cover, the band was spotted by Brian Slagel, a former music journalist who had recently founded Metal Blade Records. Slagel met with the band backstage and asked if they would like to be featured on the label's upcoming Metal Massacre III compilation; the band agreed. The band's appearance on the compilation created underground buzz, which led to Slagel signing the band with Metal Blade Records. Recorded in Los Angeles, California, Show No Mercy was financed by vocalist Tom Araya, who used his earnings as a respiratory therapist, and money borrowed from guitarist Kerry King's father. King says the album is "fuckin' Iron Maiden here and there". Vocalist Araya asserts Venom, Judas Priest, Iron Maiden, and Mercyful Fate were big influences on the record, as guitarist King was into the Satanic image.

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Wikipedia