Prog fans, prepare to make a tough decision! In the Headbanger Region of March Metal Madness we've got two progressive legends squaring off, looking to advance to Round 2 as we look to crown the Best Debut Metal Album of All Time!

Taking the dirge-laden aesthetic of grunge and combining it with complex rhythms and time signatures, Tool had a recipe for mainstream success. Despite the technicality of the music on Undertow, the band remained accessible on the surface with their early success driven by time-tested tracks like "Sober" and "Prison Sex."

Opeth's Orchid may not represent the Opeth that fans came to know and love as they contributed groundbreaking albums later in their career, but the debut is still heralded as one of the band's best. Flush with fluttering harmonies and daring compositions, this album foretold later greatness with the mix of extreme metal and subtle nods to what would become their full-blown obsession with '70s prog.

So which album will move on to Round 2 of March Metal Madness 2017? Vote below for either Tool’s Undertow or Opeth’s Orchid as the Best Debut Metal Album of all time in the poll below!

(Voting in Round 1 will end on Friday, March 17, at 10AM ET. Fans are able to vote once per hour, so keep coming back to make sure your favorite debut album advances to the next round!)