It's about to get heavy in here. This pairing of the 2013 Loudwire March Metal Madness Devil Horn Region has Tool's intense 'Ænima' album doing battle with Lamb of God's pummeling 'Ashes of the Wake' in Round 1 of the challenge to determine the best metal album of all-time.

Tool broke out with their 1993 album 'Undertow,' but their 1996 follow-up, 'Ænima,' took their experimental and aggressive prog-metal into further extremes. 'Stinkfist' and the title track both enjoyed significant play, while 'Forty Six & 2' and 'H.' were also released as singles. All in all, 'Ænima' proved to be a successful record for Tool, with 'Stinkfist' earning the Best Metal Performance Grammy in 1998.

The other half of this match is Lamb of God's 'Ashes of the Wake.' The 2004 album was the band's fourth studio album and it found them truly hitting their stride as a group. 'Laid to Rest' was the disc's big single, while 'Now You've Got Something to Die For,' 'Omerta' and 'Blood of the Scribe' are also standout cuts.

This could be one of the toughest first round battles of the 2013 March Metal Madness. Will you vote for Tool's 'Ænima' or does Lamb of God's 'Ashes of the Wake' earn your nod for best metal album of all-time? Vote in the poll below.

(This poll will end on Monday, March 18 at 11:59 PM EST. Fans are able to vote once per hour, so keep coming back to make sure your favorite album wins!)

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