Roots of Christian Andreu

Morbid Angel is an American death metal band based in Tampa, Florida, formed in 1983 by guitarist, primary composer and sole remaining original member Trey Azagthoth, vocalist and bassist Dallas Ward, and drummer Mike Browning. It was one of the first bands to incorporate guttural vocals, up-tempo blast beats, multiple tempo changes and a dark atmosphere. Morbid Angel was also the first death metal band to experience mainstream success in connection with being signed to Giant Records in 1992, heavy rotation of its music videos on MTV, and having the music video for the song "God of Emptiness" shown on an episode of Beavis and Butt-Head. The band's first three albums – Altars of Madness (1989), Blessed Are the Sick (1991), and Covenant (1993) – are considered classics in the death metal genre.

Slayer is an American thrash metal band from Huntington Park, California, formed in 1981 by guitarists Kerry King and Jeff Hanneman, drummer Dave Lombardo and vocalist/bassist Tom Araya. Slayer's fast and aggressive musical style made them one of the "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, who initially joined as a touring musician in 2011 before joining the band permanently after Hanneman's death in 2013; the drummer Jon Dette is a former member of the band.