If you're new to Young Thug, don't start with Slime Season. An odds-and-ends compilation with no coherent vision, the tape finds Thug rapping at a high level, but performing less consistently as a songwriter. It's not clear he even wants to be a songwriter on all these records; one gets the impression the tape's been compiled ex post facto, a few fully-fleshed out classics mixed in with studio dross. Some feel more like workouts, perhaps cut quickly during marathon recording sessions. (Initially Slime Season was to be produced entirely by London on da Track. "Ask 300", the beatmaker tweeted—a reference to Thug's label—when questioned about the more diverse production lineup of the final tracklist.) The bulk of these songs are for Thug completists, or those convinced of his infallibility. Nevertheless, Thug remains one of hip-hop's most exciting stylists, consistent even amid inconsistency, and there are moments worth savoring.

Part of the problem is that Thug's catalog has already been flooded with leaks and unofficial releases. Some of them—"Hey I" is a particular standout—are superior to many of the records here. Thug's biggest fans would be better off compiling their own greatest hits from the pile, and Thug neophytes will find this year's Barter 6 or last year's Rich Gang tape a much more consistent entryway. It's unclear why certain records made the cut and others didn't. The inclusion of Wayne feature "Take Kare" (which has been out since last year) may be yet another pointed dig at Thug's idol (the two have since had a falling out), but it was also an anticlimax. "Power", produced by London on da Track, seems like something left on the cutting room floor from the Barter sessions, and if it was, it's easy to hear why: where each Barter record made up a discrete facet of the album's sound, "Power" sounds a little bit like three of them at once—consummate filler.

In the rush to fete Thug for his radical talents, it's important to draw distinctions between what records work, and which ones do not—or those which sort of work, if you look at them from the right angle. Part of the joy of his art is that you can draw together your own version of his canon from a scattered field, picking up on the pieces that most attract you. (This is not a quality limited to Thug; it's been this way since the Internet began to reward rappers, like Lil Wayne and Gucci Mane, who could flood the market without drowning in it.) The most evident gem here is "Best Friend". Its hook is inspired by a viral vine (Tokyo Vanity, the meme's creator, has released a "Best Friend" record of her own), and its surreal video is sly and artfully unpredictable. The Ricky Racks-produced record, which builds upon disorienting sound effects and hypnotic pizzicato strings, draws you in while bringing you no closer to figuring it all out, a contradiction at the heart of the Young Thug project.

Thug's best songs are carefully structured, even if they appear effortlessly thrown together, and the most effective moments tend to be subtle, sidling up to the listener. Each of the song's parts—melodies, backgrounds, hooks, choruses, and flows—lock in to give the song a shape as particular as a fingerprint. Many songs on Slime Season don't chase this goal; at the album's opening, Thug's drawn to repetitive, headbanging patterns and the results are for hardcore fans only. The opening tracks, the Sonny Digital-produced trap banger "Quarterback" and the Southside-produced "Rarri", are interesting but lack replay value. A few of the harder-edged songs do work: "Freaky" might be its best experimental moment, with Wondagurl's unstructured, percussive beat bringing Thug's songcraft and improvisational rap style to the fore.

But the album's true highlights don't arrive until its close, with the one-two punch of "Draw Down" and "Wood Would". On the former—which has been out for some time—Thug strategically deploys different flows to shape the song, while his unpredictable figurative language keep the listener on their toes: "Pull up with that K out of the coupe! I like my bitch brown like a mu'fuckin' boot!" he says at one moment, or later: "Put that pussy on my head like a fuckin' Motrin!" Disguised in his squall of a delivery, they're not conveyed as jab-you-in-the-ribs punchlines; they're playful and impossible to anticipate, chasing novelty rather than cliche, lending the song an uncertain, volatile air.

As for "Wood Would", it's the album's strongest, and stands among the best in his catalog. With its sample skipping like a stone as its drums slam in place, it's low-key and unassuming, evading direct translation and shifting in and out of lucidity. Yet Thug wears his heart on his sleeve through one of pop's oldest tools: an undeniable melody. It says everything he doesn't need to, as if everything you didn't know were clear as day.