The Arkansas quartet Pallbearer pushes at the rigid strictures of doom metal with warped rhythms and cosmically dense songs. On “Thorns,” the lead single from their third full-length album, Heartless, they trade in gloom for heavy, memorable hooks. Creeping, downtuned chords—a constant of the band—pair with guitar work that’s more meticulous and flashy than before. Delicate leads shimmer and spark; ornate guitars unfurl majestically, like a medieval tapestry. Their music retains that same crushing weight, but on “Thorns,” they’ve dipped their harrowing harmonies in gold.