Metallica frontman James Hetfield has praised Black Sabbath guitarist Tony Iommi as the “riff lord” and the greatest influence on his rhythm guitar playing and songwriting. Speaking on his SiriusXM programme, Hetfield explained how Iommi’s “Children of the Grave” riff demonstrates his distinctive approach to building songs around powerful guitar parts.

Hetfield has repeatedly acknowledged Iommi’s influence, including during Black Sabbath’s 2006 Rock & Roll Hall of Fame induction. Metallica recently performed at a tribute event for Ozzy Osbourne and Black Sabbath, and will begin a 24-night Las Vegas Sphere residency in October, continuing until March 2027, before resuming their M72 World Tour in North America in May 2027.