The mighty masters of morbid rock have returned (again). Sabbath bear the responsibility for some of the most monstrous riffs ever created, and there aren't many contemporary rock bands who are totally free of their influence, so a huge tour and a new album ('13' – named after the year, since they actually released their thirteenth record in 1987) are a welcome reminder of just how important they've been to the development of rock, metal and grunge. Sadly drummer Bill Ward dropped out last year, but apart from that the Sabbath line-up on show is the same one that came together in Birmingham in 1968. That means Tony Iommi and Geezer Butler playing towering guitar lines at ear-splitting volumes, plus Ozzy Osbourne's crazed screams and zombie-like jerks. Raise the horns.