Over the weekend, Tool headlined the Saturday edition of 2015 Monster Mash Music Festival in Tempe, Ariz., and in the spirit of Halloween, dressed up as Led Zeppelin. They took the costume bit to the next level, opting to open their first and only show of the year with a cover of Zeppelin's "No Quarter" off Houses of the Holy. The psychedelic song falls in line with Tool's music and has been played live since the early '90s, and even appeared on the band's 2000 box set Salival.

Maynard James Keenan donned a blond wig, sunglasses, an oversized belt buckle, a tan jacket, and just like Robert Plant, left his torso bare and remained in costume throughout the entire set. Of course, the singer is no stranger to wearing costumes onstage, which can not be said for the rest of the band. Adam Jones even used a double neck guitar to complete his Jimmy Page ensemble. While the Jones and bassist Justin Chancellor abandoned their costumes after the cover, drummer Danny Carey was the only other member to remain dressed up after finishing the Zeppelin tune, but he too shed the costume later on, freeing himself up for his drum solo.

Tool treated fans to some rarities at the show, following up "No Quarter" with "The Grudge," "Parabol" and "Parabola." Performing for two hours, the band also tore through classics like "Ænimaand "Jambi" and even appeared to debut an instrumental jam of a new song, "Descending."

Opening the show were Primus, Coheed and Cambira, Æges and With Our Arms to the Sun.

With the band only performing one show this year, the big question on the mind of every fan is "when will Tool be releasing a new album?" It has been nearly a decade since any new material has been released and while the band have confirmed they are hard at work on another album, not much has been confirmed as far as the progress is concerned. Keenan has been especially frustrated with all the interviews asking about the state of the upcoming album.

In one interview, he was asked to provide an update on Jones saying they almost had one song done, stating, “Do I seem like a lazy person? That’s all I can really say. They’re working hard in their own way; I’m working hard in my own way, and I’ve got nothin’ for ya.”

Tool 2015 Monster Mash Music Festival Setlist

"No Quarter" (Led Zeppelin)
"The Grudge"
"Descending" (Instrumental)
"Forty-Six & 2"
Drum Solo
"(-) Ions" (recording)

Tool Perform 'Descending'

Maynard James Keenan as Robert Plant

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