This fourth and final matchup in the President of Heavy Metal election quarterfinals features metal music's maddest scientist, Maynard James Keenan. It's difficult to categorize the music of Tool, other than it sounds like Tool, but the band's experimental and progressive brand of metal has cemented the group as one of modern metal music's finest acts. Plus, it would be pretty amazing for metal's White House to be built on an Arizona vineyard.

Iconic Black Sabbath vocalist and solo artist Ozzy Osbourne aims to claim yet another heavy metal title. Already dubbed the 'Prince of Darkness,' Ozzy is now competing for the title 'President of Heavy Metal.' Ozzy defeated the election's only intergalactic candidate in GWAR's Oderus Urungus, but now he's got Keenan's cult fans to compete with.

Maynard James Keenan or Ozzy Osbourne? Cast your vote for the President of Metal in the poll below! Voting for this round ends on Monday, Oct. 29 at 10am ET. Fans can vote once per hour, so keep coming back to make sure that your favorite metal musician wins!

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