Testament is an American thrash metal band from Berkeley, California. Formed in 1983 under the name Legacy, the band's current lineup comprises rhythm guitarist Eric Peterson, lead vocalist Chuck Billy, lead guitarist Alex Skolnick, bassist Steve Di Giorgio and drummer Dave Lombardo. Testament has experienced many lineup changes over the years, with Peterson being the only remaining original member, though they have since been rejoined by one of its songwriters Skolnick, who had been out of the band from 1992 to 2005. Billy has been a member of Testament since 1986, when he replaced original singer Steve "Zetro" Souza, who had joined Exodus as the replacement of Paul Baloff. He and Peterson are the only members to appear on all of Testament's studio albums, with the latter being the only constant member overall.