The album consist of three death metal songs. The song "Bells of Doom" was later included in a 2001 fan-club compilation album named the same as the song, Bells of Doom.

Paroxysmal Holocaust was recorded during March and April 1989 in the little Swedish 8-track studio Sveastrand. Christofer Johnsson, founder and only all-time band's member, had mixed opinions of this demo album. At the Therion official website he mentioned the band was excited because of the first release ever, although he was very critical to this recording claiming the album "was awful":

As we had never been in a studio before we were anyway very happy with the recording. Kind of "Wow we can hear our songs coming from a tape". But in reality this demo was awful in my own opinion. But what the heck, we had the studio for free and many people liked the demo back then.

Beyond the Darkest Veils of Inner Wickedness is a title of a Therion's 1989 demo. The album was released on November 1989 on a cassette, limited to 500 copies.

The album consist of three death metal songs. Two of them, "Macabre Declension" and "Paroxysmal Holocaust", were later included in 2001 official fan-club compilation Bells of Doom. Song "Paroxysmal Holocaust" recorded live in Strömstad, Sweden, 1989 was included in 2006 box-set compilation Celebrators of Becoming.

Beyond the Darkest Veils of Inner Wickedness was recorded and released in the same year (1989) as the band's first demo album Paroxysmal Holocaust. The album was recorded in a Swedish 16-track studio.

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Wikipedia