Prior to joining Metallica, guitarist Kirk Hammett was originally a member of Exodus, a band he had co-founded as a teenager. In a look back on Metallica's Ride the Lightning album, he admitted he felt some guilt when he made the decision to jump ship in 1983, but harbored no ill feelings about repurposing some of his riffs.

Hammett and drummer Lars Ulrich offered a track-by-track reflection on each song off Metallica's 1984 sophomore album in a recent Metal Hammer feature. "Trapped Under Ice" sports a riff Hammett originally wrote for the Exodus song "Impaler" (which first officially appeared on Exodus' 1997 live album Another Lesson in Violence and later on 2004's Tempo of the Damned) and it's leaving his high school friends behind that bothered him, not reusing the riff.

"[The riffs] came from songs I had written, music I had written. I consider them my parts," Hammett stood firm.

"I didn’t feel guilty about that," he admitted, "but I did feel guilty about leaving the band I started in high school. I’ve known [Exodus drummer] Tom Hunting since I was 16 years old, I’ve known [Exodus guitarist] Gary Holt since I was 17. We’re all close to this day, but there was a lot of guilt there for a while. A little bit of remorse."

Still, it was a purposeful move that obviously worked out for Hammett, especially now that he conceded, "But I really felt that Metallica was my calling. I felt more comfortable playing in Metallica than I ever did in Exodus, so go figure."

As part of the ongoing #MetallicaMondays series which finds Metallica uploading full concert videos from past performances each week, the band recently dusted off a 1983 gig, which was taken from their first-ever tour. The show was shot just a few months after Hammett's audition.

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