Guitars playing abrasive, discordant riffs, the thunderous double-kick of the drums acting like an accelerated heartbeat, and porcine, guttural vocals pummeling twisted lyrics. Courting controversy from inception to its modern day iteration, death metal presents a number of contradictions: Driven and adventurous musicians compete to make uncomfortable noises; it is crude and far beyond parody and yet consistently popular; and the music is pig-headedly uncommercial despite making a few labels, albeit briefly, wealthy.