This Devil Horn Region matchup in March Metal Madness to determine the Best Debut Metal Album of All Time is especially interesting considering how Slayer would eventually pave the way for death metal and acts like Morbid Angel. In Round 1, it's Show No Mercy vs. Altars of Madness!

Before Slayer became the dominant thrash force they're now known as, they still had some New Wave of British Heavy Metal influences to get out as they began to carve their own sound. Tom Araya's darting vocal delivery provided a sense of danger as torrents of riffs scurried past these rapid phrases and the hallmarks of the band were falling into place on cuts like "Die by the Sword" and "Black Magic."

The '80s only offered a handful of full-fledged death metal albums and Morbid Angel's defining Altars of Madness was among the top of this small but influential heap. Evil incarnate, the band's sound hinged on Pete Sandoval's unmatched double kicks and tense blast beats while Trey Azagthoth upheaved mounds of Earth with his riffing might, exposing the glowing contents of the planet with "lava," a term he would later use to describe his solos.

So which album will move on to Round 2 of March Metal Madness 2017? Vote below for either Slayer's Show No Mercy or Morbid Angel's Altars of Madness 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!)