The Las Vegas pop-rockers had a legit claim to the title of Biggest Band in the World in the stretch between their debut album, 2012’s Night Visions, and its 2015 follow-up, Smoke + Mirrors. It seemed that Imagine Dragons had skipped the “humble upstart” phase and proceeded straight to full-blown arena-rock spectacle with their blend of Coldplay-esque schmaltz and Obama-era Americana of the “stomp-clap-hey!” variety, with a pinch of EDM thrown in for maximum festival appeal. Smoke + Mirrors became the Dragons’ first album to debut atop the Billboard 200, buoyed by a lead single, “I Bet My Life,” that still feels omnipresent on rock radio, and in Truck Month commercials. Ten years later, Reflections celebrates their sophomore album’s anniversary with 13 unreleased tracks from the original recording sessions, plus a folksy demo version of “I Bet My Life.” The band wrote a good deal of Smoke + Mirrors on the road during their massive, 170-date 2013-2014 world tour, which might explain the “Imagine Dragons on island time” riddims of “Woke” or the French touch of “Monica,” a disco number about letting a date down easy. Needless to say, the Dragons let it all hang out here, from the “Kraftwerk meets filthy dubstep drops” of “The Ghost Intervention” to the experimental noise-rap of “I Get Carried Away.”