Despite signing to a major label years earlier, Mastodon really didn’t lumber into the mainstream until 2011’s The Hunter. At that point, the band had completed the migration to clean singing and mostly shed its prog-rock eccentricities. Once More ‘Round The Sun followed, still bringing the heavy but incorporating even more melodic elements. Had that record been a double, it could’ve easily shared album gatefolds with Mastodon’s latest. Emperor Of Sand hears the band’s continued evolution (de-evolution?) from metal to hard rock, its destructive powers diminished in the pursuit of accessibility. In chasing commercial appeal, drummer Brann Dailor remains the band’s most capable vocal weapon, with the earworm-y “Steambreather” recalling Once More’s “The Motherload.” Elsewhere, the only real blunder here is “Clandestiny,” which is sadly reminiscent of Styx (ask your parents) in its middle section. Emperor is solid, dexterously played hard rock from a band that used to crush listener skulls.