For its fifth studio album, Georgia’s Mastodon refines its attack, replacing epics of more than 10 minutes with tunes that put it together in no more than five and change. Tracks like “Curl of the Burl” and “Stargasm” have an accessibility that’s recently been largely absent. The intricate guitar work of “Octopus Has No Friends” heightens Brann Dailor’s ambitious, jazz-like drumming. Dailor’s actually the secret weapon here, adding his unpredictable patterns to songs until they walk off on their own. “All the Heavy Lifting” could be a standard-issue tune if not for Dailor bringing the apocalypse. Astral meditation underscores “The Hunter.” Black Sabbath inspires the tribal/stoner vibe of “Creature Lives.” Neurosis singer/guitarist Scott Kelly joins the group for the pummel of “Spectrelight.” These aren’t the same old stoner riffs but reinventions of sound from a band that’s found an edge and persona all its own. The album’s deluxe version features two notable bonus tracks, “The Ruiner” and “Deathbound,” which are as heavy as anything the band has recorded. Essential listening for all Mastodonians.