They had a big influence on early Swedish death metal, along with Obscurity as well as Merciless shortly thereafter.
[1] Mefisto originally consisted of three members: guitarist Omar Ahmed, drummer Robert "Thord" Granath, and singer Sandro Cajander.
Cajander, who later joined Morbid, had a deep, harsh vocal style comparable to but more extreme than peers Bathory or Venom, which was developed further by LG Petrov of Nihilist (later Entombed).
The band has since gained cult status, heavily influencing the upcoming extreme music underground, especially the Stockholm death metal scene.
[2] These demos, which were reissued as a compilation CD entitled "The Truth" on Regain Records in 1999 form a prototype for Swedish death metal.