Rigorously avoiding interviews, Mostack has let his music do the talking. Rightly so: alongside 2016’s Gangster with Banter mixtape, features on J Hus and Tinie Tempah records have cast the North Londoner as one the UK’s sharpest MCs. This mixtape only enhances that reputation, with his low-key delivery rolling out smart wordplay to luminous Afrobeats melodies on “Ussy Ussy” and “I Like It.” Meanwhile, “The Friend,” a disarmingly honest ode to solitude set to woozy acoustic guitars and tablas, underlines his individuality and invention.