The only problem was that in the late-'90s, when the album was being written and recorded, Iommi had no idea who Eminem was, according to Loudwire, which was at Iommi's Musicians Institute sit-down Monday (Oct. 23).
The request wasn't totally out of the blue; Iommi had booked the services of a number of guest vocalists, including another hip-hop legend, Ice-T, and even another Detroit-based rapper, Kid Rock (whose song didn't make the album's final cut).
Eminem, of course, was a pop-culture phenomenon by 1999, when his second full-length album, The Slim Shady LP, was released.
Some of the other guest contributors to Iommi included Dave Grohl, Henry Rollins, Phil Anselmo, Billy Corgan, Serj Tankian and Brian May.
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