James Hetfield of Metallica has praised Tony Iommi of Black Sabbath as the guitarist who has inspired him most, describing Iommi as "the riff lord" during an episode of his "Riff Life" show on SiriusXM. Hetfield specifically highlighted the "Children of the Grave" riff as exemplary of Iommi's masterful composition and arrangement, emphasising its influence on his own rhythm guitar playing and songwriting.

The article provides historical context for this enduring admiration, recalling a 1992 interview in which Hetfield described discovering Black Sabbath through his older brother's record collection as a child and being immediately captivated by their anti-establishment sound. Hetfield's deep emotional connection to the band was further evident in his 2006 Rock and Roll Hall of Fame induction speech, during which he became tearful whilst recounting how Sabbath's "monstrous riffs" had profoundly shaped him as a musician and ultimately made Metallica possible; Lars Ulrich similarly credited Black Sabbath as foundational to heavy metal itself.