Satanicum Tenebrae is a obscure Dark Ambient project by Lord Meyna'ch (Willy Roussel), leader and mastermind of Mütiilation. (He has also been member of Hell Militia, Malicious Secrets, Gestapo 666).
Satanicum Tenebrae was part of the Black Metal underground French group Les Légions Noires (the Black Legions) along with Vlad Tepes, Belketre, Torgeist, Black Murder and many other bands.
Satanicum Tenebrae released 3 demos:
Til Helvete (1994)
Voices of the Dark Call Me to Suffer (1994)
NOTE: Contrary to what some people say (and also Metal Archives) Satanicum Tenebrae was NEVER called Belathuzur. Belathuzur is a totally different project (Black Metal and not Dark Ambient) led by Mütiilation ex-drummer Krissagrazabeth, as Wlad of Vlad Tepes says in the interview with Petrified Magazine back in 1994.