Prairie Fyre is that rare doom-metal band that features a viola. Yes, a viola. The group is fronted by the booming bass and roaring guitar and vocals of twin siblings John and David Leppke with Brady Madden on drums and Emily Smith on viola. That’s right, a viola. The band puts an emphasis on gut-shaking rhythm and an air-raid atmosphere during a typical performance. It also works to answer the long-standing and seemingly impossible headbanger’s question: What would early Black Sabbath or Tool sound like if Tabea Zimmermann was in the band? That’s Tabea Zimmermann, the great German violist. You knew that, right?