Nineteen-year-old Florida rapper Kodak Black has always been blessed with a slurred, frog-like croak—though he’s had trouble differentiating himself from similarly drawling Southern forefathers like Boosie Badazz and Gucci Mane. After making a splash with two viral hits, “No Flockin” and “SKRT,” he released three good-not-great mixtapes, all of them overlong and generally indistinguishable from many of his contemporaries. His latest tape, Lil B.I.G. Pac—recently released on his birthday as the young rapper sits behind bars—fixes this. It's punchier; the themes are weightier; the emotional range is more dynamic. And it finds Kodak Black sounding like nobody but himself.

On the tape, Kodak offers a highly pleasurable mix of introspective, gripping street rap, free-flowing punchlines, youthful swagger, and even hints of an old soul. Though Gucci Mane and Boosie appear as guests, their presence does not lead to shallow comparisons; rather than being a copycat, Kodak is now living up to their legacies. His flow snakes its way through Southern-fried productions with a sleepy effervescence, where he drops punchlines and subtle turns of phrase with a Gucci-like sensibility: “Grinding for a mil’ and I ain’t talking ‘bout a combo/My mama need a crib, I been thinking ‘bout a condo,” he offers on mission statement “Everything 1K.” Oftentimes, food-based imagery lands the hardest: “Drop two ounces of codeine in my Minute Maid,” or “I be on that Little Ceasars shit, hot and ready,” or, on the buoyant, bristling “Today,” he raps, “I might lace the birthday cake with molly.”

But it’s the thoughtful, throwback street raps that linger after the party has ended. On crawling summer anthem “Can I,” Kodak oozes pathos over a gorgeous beat co-produced by Honorable C.N.O.T.E. and Derelle Rideout: “Can I ball, can I chill? Can I stunt? Will I live long enough to raise my son?” Though he’s rapped like this before, the potent combo of his laconic delivery and his natural voice has never sounded so affecting.

Penultimate track “Letter” twists a few new wrinkles into the idea of a hip-hop song written from the perspective of someone in prison: The first verse finds Kodak reflecting on a letter he receives while in jail, while the second sounds like the note itself. It’s a nuanced portrait of camaraderie, and by voicing his own feelings against the backdrop of what his friend is writing to him, the track illustrates the wistfulness and uncertainty of two young people living their lives apart. Kodak says fondly, “He remember them times going on them missions/Say he for real, he reminiscing.” Then later, from the other perspective: “You my lil nigga forever, just keep your head up.” In just about two and a half minutes, Kodak weaves the story, and you gain the full picture of friends struggling to stay afloat, drifting from jail to a tempestuous street life. It’s a disarming emotional display from someone so young.

However, much like his stellar collaboration with French Montana earlier this year, “Lock Jaw,” it’s Kodak’s ability to keep up on any beat while flexing his lyricism and unique flow that makes him a compelling artist. This is evident on single “Vibin in this Bih,” where he handily floats atop a frisky instrumental. “Hittin’ licks, now I’m dropping hits, mouthpiece cost a brick,” he raps on the track, before Gucci responds, “Walk around the club like I walked around the yard.” It’s telling that Kodak is one of a handful of rappers Gucci has worked with following his recent release from prison; he sees the talent and vision in this kid. And with Lil B.I.G. Pac, that vision is clearer than ever.