Additional personnel: Geoff Nicholls (keyboards).

Recorded at The Record Plant, Los Angeles, California.

Composer: Geezer Butler.

Black Sabbath: Ronnie James Dio (vocals); Tony Iommi (guitar); Geezer Butler (bass guitar); Vinny Appice (drums).

Arranger: Geezer Butler.

Black Sabbath had put itself back on track both musically and commercially with the 1980 album HEAVEN AND HELL, as the addition of new vocalist Ronnie James Dio was the shot in the arm Sabbath needed. A follow-up was released one year later, MOB RULES, which follows in the same mega-decibel approach as its predecessor. While it is still a vast improvement over Sabbath's final two albums with Ozzy Osbourne (1976's TECHNICAL ECSTASY and 1978's NEVER SAY DIE), it doesn't exactly match the inspired performances and top compositions featured on HEAVEN AND HELL.

The opening track, "Turn Up the Night," kicks off the album with a jolt of electricity, while other hard rocking highlights include the mid-paced "Voodoo" and the raging title track--the latter would be featured on the soundtrack to the cult animated movie, HEAVY METAL. Another standout was the near eight-minute epic "The Sign of the Southern Cross," which starts as a gentle acoustic composition, before transforming into a classic slice of plodding Sabbath metal. Although Dio had been a major factor in returning Sabbath back from the dead, he would leave the group under less than amicable circumstances after the release of the 1982 live album LIVE EVIL.