G//Z/R is a band led by Birmingham born Black Sabbath bassist/lyricist Geezer Butler. The bands music is generally of a much harder edge than Butler is known for in Black Sabbath. This isn't a surprise, as the vocalist on his first album, Plastic Planet, was Burton C. Bell from Fear Factory, who is known for more driving and harder edged vocals than ever was displayed in Black Sabbath. The album also featured Pedro Howse on guitar, as well as Deen Castronovo (of Journey fame) on drums. Bell did not stay with the band past the recording of Plastic Planet due to Fear Factory commitments.