So is a gnarwhal a whale that shreds the gnar? And what does the whale shred? Does the whale shred with its tusk? These are hard-hitting questions for Gnarwhal, but the Nashville guitar-and-drums duo only responds with wild yelps, frantic guitar work and crashing drums.

"Light-Up City" comes from the band's third album, Crucial, and it's a raw and switchback-crazy seven minutes of chaotic math-rock. Drive Like Jehu's most emotionally wrought moments come to mind, but stripped down to the bare essentials.

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