It may be hard to believe, but Slipknot were once a relatively unknown band. Slipknot purists may consider 'Mate. Feed. Kill. Repeat.' to be the act's first album, but Slipknot themselves have credited their 1999 self-titled effort as their official debut.

Slipknot's self-titled album proved as perhaps the most significant launching point for any band in the past 15 years, the disc containing fan favorites 'Eyeless,' 'Wait and Bleed,' 'Spit it Out' and 'Surfacing.' The debut has gone on to sell over two million copies in the U.S. alone.

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