Monotheist is a comeback album by Swiss metal band Celtic Frost, released in 2006. It is the first new recording released by the band in 14 years. Preparation and development work for this project had been ongoing since 2000, originally inspired by Celtic Frost's involvement in the acclaimed 1999/2000 highlighting official album re-issues. Compared to Celtic Frost’s previous works, Monotheist possesses a heavier, much darker atmosphere reminiscent of doom/gothic metal, and eschews much of the Thrash sound of their early work. According to the band's bassist, Martin Eric Ain, some of the lyrics are partially influenced by the writings of the English occultist Aleister Crowley. This influence manifests itself in tracks such as "Os Abysmi Vel Daath", which is partially a name of one of Crowley’s books. The final track, “Winter (Requiem, Chapter Three: Finale)” is the concluding part of Celtic Frost's requiem, which began with "Rex Irae" from 1987’s “Into the Pandemonium”. The second part has yet to be released by the band. Monotheist is available in a Digipak version with a bonus track, called "Temple Of Depression". Both the vinyl LP version and the Japanese CD release of Monotheist feature the bonus track “Incantation Against You”. A video was made for the song "A Dying God Coming into Human Flesh" Working titles for the album included "Probe" and "Dark Matter Manifest". Monotheist was number 2 on music magazine Terrorizer's list of the best albums of the decade. The in