Roots of Threshold

Pain of Salvation is a Swedish progressive metal band led by Daniel Gildenlöw, who is the band's main songwriter, lyricist, guitarist, and vocalist. Pain of Salvation's sound is characterised by riff-oriented guitar work, a broad vocal range, oscillation between heavy and calm passages, complex vocal harmonies and the structures of their albums, syncopation, and polyrhythms. Thus far, every album released by the band has been a concept album. Lyrically, the band tends to address contemporary issues, such as sexuality, war, the environment, and the nature of God, humanity, and existence.

Eldritch is a progressive metal band formed in 1991 in Italy.

Testament is an American thrash metal band from Berkeley, California. Formed in 1983 under the name Legacy, the band's current lineup includes rhythm guitarist Eric Peterson, lead vocalist Chuck Billy, lead guitarist Alex Skolnick, bassist Steve Di Giorgio and drummer Chris Dovas. Testament has experienced many lineup changes over the years, with Peterson being the only remaining original member. The band has released fourteen studio albums, four live albums, five compilation albums, thirteen singles and three DVDs. They are estimated to have sold over 1.4 million albums in the United States since the beginning of the SoundScan era, and over 14 million copies worldwide as of 2016.