The records of Young Thug, a.k.a. Jeffery Williams, continue to command the rap zeitgeist, in part because there’s so many of them. (Jeffery is his third full-length release this year.) But the real secret to Thug’s success is musical: the wild, mush-mouthed flow pours out in songs like “Webbie,” a typically skewed sex-and-drugs boast, and the stormy “Harambe,” which puts this usually strict amoralist at the center of a soul-tussle between God, the devil and Godzilla. Jeffery may be Thugger’s strongest collection since 2014, in part because of the production, which in several songs adds a reggae bounce to booming trap beats. But as usual it’s Thug’s own sound that predominates: the heroic howls, rasps, mumbles and wheezes of a man who is as captivating a vocalist as any in pop.