Pink Floyd's creepy "Careful With That Axe, Eugene" takes on Donovan's spooky "Season of the Witch" 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.

Released as the B-side to the 1968 Pink Floyd single "Point Me at the Sky," and later featured on both Ummagumma and Live at Pompeii, the band-written "Careful With That Axe, Eugene" is a sweeping instrumental that takes listeners to strange and violent places. And all of that happens without anybody in Pink Floyd ever saying a word, though there was usually a lot of screaming from Roger Waters.

"Season of the Witch," meanwhile, represented a pioneering moment in psychedelic rock from Donovan's 1966 album Sunshine Superman – and, maybe, an early hint at what was to come with a band called Led Zeppelin. Jimmy Page, then an ace sessions guy, provides the ghostly guitar work and (if persistent rumors are to be believed) John Paul Jones perhaps added keyboards.

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 Pink Floyd Perform 'Careful with That Axe, Eugene'

Listen to Donovan Perform 'Season of the Witch'

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