In early 2011, Chief Keef’s name didn’t resonate outside of Chicago’s South Side. But to the thousands of Chicago Public School kids who listened to his songs obsessively, the teenage rapper was already a superstar. And with the release of Bang that fall, the rest of the world would catch up to a kid so self-assured, he was already referring to himself as “the famous Chief Keef.” A striking introduction to the now iconic rapper’s style, Chief Keef’s debut mixtape features catchy hooks, battle-cry beats, and plentiful “bang bang” ad-libs, painting a complete picture of the 16-year-old’s world. (That youthful energy permeates the album: Bang was produced in its entirety by DJ Kenn, a Japanese hip-hop head who’d moved to Chicago and fallen in with Keef’s crew by sheer chance.) The title track would become Keef’s breakthrough hit—an eerie riff on the producer Lex Luger’s blustering trap sound that would catch the ears of local media and then the world. But Chief Keef already seemed to know where he was headed. On “Setz Up,” a track whose giddy menace sets the tone for hits to come, he makes a casual (and prophetic) pronouncement: “We don’t believe in luck, but I’m next up.”