Before Corrosion of Conformity became famous for their heavy metal style, they were a punk rock band, specifically for their 1984 debut album "Eye for an Eye". On their 1985 follow-up "Animosity" and 1987 EP "Technocracy", C.O.C. transitioned from punk into crossover thrash, and eventually became a thrash/stoner/sludge metal band on their future releases.