If they wanted to, Norway's Mayhem could just coast on their past till the end of time and stay up on a pedestal as one of the most important extreme metal bands ever. Mind you, that would have as much to do with the black metal band's mythic history outside the recording studio as it would with their music. I guess that all comes with the territory when your first singer kills himself (and a remaining band member eats some of his brains before the police show up), your second singer is murdered by the most notorious scenester in town, and another recent vocalist likes to decorate the stage with real pigs' heads. All that aside, after being around in various shapes and forms for over 20 years, Mayhem are still atop the genre they helped create, playing raw, dissonant, lo-fi metal and writing cohesive, complete-sounding records. Current singer Attila Csihar basically groans, snarls and moans, using his voice as a visceral instrument. With its deeply unsettling tension and scathing anger, Ordo affords the listener no real break until you hit the stop button.