Metallica's James Hetfield cited two of his early guitar influences. Loudwire reported during the promotional video for Hetfield's new Hardwired Master Core strings for Ernie Ball, he explained how both metal and punk icons helped lead the way to his unique style of rhythm guitar.
Hetfield was quoted as saying, “For me it was a little more raw, the stuff that I liked. Discovering bands like AC/DC then Judas Priest and then the whole new wave of British heavy metal came out and that was Iron Maiden, then Motorhead, and Black Sabbath for sure was a Number One influence for me. Seeing that first album cover, and seeing that first Iron Maiden album cover, it drew me right to it. I just got continually heavier and heavier as I was discovering music.”
Hetfield went on to shed light on the mechanics of his guitar playing: “I'm kind of a little bit of a barbarian when I play. I'm always interested in the riff. It was the foundation of the song. Tony Iommi, he's ruling the song with his riff and everything else joins him. Y'know, Johnny Ramone, lots of down picking lots of y'know, just fast down picking. That helped develop my style. So kind of a combination of punk rock and heavy rock at the time y'know, turned into just the down picking style and with melody along with it.”