 Metallica and Slayer, pioneers of the heavy metal subgenre thrash metal, were influenced by a number of hardcore bands.Metallica's cover album "Garage Inc." included covers of two Discharge and three Misfits songs, while Slayer's cover album "Undisputed Attitude" consisted of covers of predominately hardcore punk bands.The Washington state band Melvins, aside from their influence on grunge, helped create what would be known as sludge metal, which is also a combination between Black Sabbath-style music and hardcore punk.