Black Sabbath's eponymous sludge fest takes on Alice Cooper's signature "Welcome to My Nightmare" in round one of our Rock's Scariest Song battle.

In honor of Halloween, we've chosen 16 of rock's scariest songs. The field will be sliced, diced and chopped in half every week based on your votes, until only the scariest song in rock history remains alive.

Black Sabbath's "Black Sabbath," from their album, um, Black Sabbath, pretty much helped seal the band's reputation as devil-worshiping evildoers. The 1970 song sounds like a little piece of hell chipped away from its dominion and tossed on earth to fester. The slow, sludgy crawl over six minutes is menacing, to say the least, and Ozzy Osbourne comes off like a man possessed in his delivery.

"Welcome to My Nightmare," similarly, plays along a similar dirge-like path at first. The song was the opening track and title song of Cooper's eighth album, which was released in 1975. It marked his first LP as a solo artist, and the song stands as an introduction and theme to his new persona. The track eventually picks up the pace, including elements of jazz, pop and, gulp, disco into its mix -- which is also kinda scary.

You can listen to both songs below so you can make an informed choice. You can vote once per hour in each of the eight first round Rock's Scariest Song battles until polls close on Oct. 12 at 11:59PM ET. Your choice for Rock's Scariest Song of all time will be revealed on Nov. 1, 2015.

Listen to Black Sabbath's 'Black Sabbath'

Listen to Alice Cooper's 'Welcome to My Nightmare'