Black Sabbath generated one of the biggest comeback albums in metal history with 13, which was led by the lengthy single "God Is Dead?" Opeth and their track "The Grand Conjuration" are up against the godfathers of metal in the Headbanger Region of March Metal Madness in a battle to advance to the next round of our tournament to determine the Best Metal Song of the 21st Century.

The doom lords from Birmingham returned with their first album to feature Ozzy Osbourne behind the mic since the ill-fated 1978 effort, Never Say Die! "God Is Dead?" brought them back to their early days, bouncing between tectonic riffs and eerie, clean picked guitar lines that convey a haunting atmosphere. Ozzy's nervous energy captures the magic as Tony Iommi and Geezer Butler move mountains with their respective tones.

Opeth are tasked with trying to overtake Black Sabbath, but their legion of diehards have the ability to pull out a victory here. "The Grand Conjuration" comes off their landmark Ghost Reveries album and runs through a myriad of soundscapes over the course of its 11-minute duration. Elements of '70s prog rock collide head on with the death metal foundation the band laid out a decade earlier. Mikael Akerfeldt's gutturals are possibly the best in the business and his timid clean voice has a charm like nobody else.

So which song will move on to the second round of March Metal Madness 2016? Listen to both tracks and vote for either Black Sabbath's "God Is Dead?" or Opeth's "The Grand Conjuration" as the Best Metal Song of the 21st Century in the poll below!

(This poll will end on Tuesday, March 8, at 9AM ET. Fans are able to vote once per hour, so keep coming back to make sure your favorite song wins!)

Black Sabbath, "God Is Dead?"

Opeth, "The Grand Conjuration"