Never mind the artwork or the title, the chief concern of Iron Maiden’s 15th album is Earth — specifically, the end of it: “There will be a catastrophe the like we’ve never seen,” warns Bruce Dickinson on the album’s 11-minute closing track, and by the time we get there, we’ve seen rivers flowing with blood, ominous comets and unhappy phantoms. The music that accompanies these visions is suitably apocalyptic: The riffs on “El Dorado” gallop like the Four Horsemen, and grim war saga “Mother of Mercy” is built on stark, wailing guitars. Maiden have long had a knack for the lung-busting chorus, but what impresses here are the complicated arrangements. “The Talisman” takes a full nine minutes to unfold, elegiac synths giving way to hammering chords. So much for the world ending with a whimper.