The Atlanta rapper Casino is brothers with Future, the reigning king commercially accessible, emotionally resonant Auto-Tune burps. This, in itself, is not a good enough reason to pay attention to Casino. And Casino, to his credit, seems to be realizing this. It took a little while. Last year, Casino released Ex Drug Dealer, which somehow managed to be a painfully boring mixtape despite having Future on about half its songs. But Casino is learning, figuring things out, starting to show a forceful personality that has nothing to do with his brother. Last week, Future gave Casino his biggest look since the original version of “Karate Chop,” or possibly ever. Casino showed up last on the ridiculously great Future/Pusha T/Pharrell throwdown “Move That Dope,” saying nothing worth quoting but yelling louder than anyone else, rapping so hard it seemed like he might lose his hair or burst an eyeball. That was just an early taste. And with Frank Matthews, his new mixtape, Casino has effectively reinvented himself as a goofily boisterous shout-rapper. He’s also replaced Nas’s brother Jungle as the greatest “tougher, less talented brother of a famous rapper” figure in rap history.

Casino isn’t a remotely subtle rapper, but the differences between 2013 Casino and 2014 are subtle. Back then, his voice rang out loudly, but he also sounded disconnected and rote, robotically kicking out all the moving-weight stuff you’d expect. He’s still loud now, but all of a sudden he’s also engaged, finding joy in ways to say all the same stuff. The tape is named for a notorious ’70s drug trafficker, and sampled talking heads show up throughout to talk about what an important drug dealer this guy was, so we’re on familiar ground, subject-wise. But Casino is now practically giddy when talking about this stuff. He’s not going to dazzle anyone with his lyricism; the best we can hope for is a silly-fun punchline every so often: “Got some big guns hanging from my arm like I’m Robocop / Casino transform into a killer like a Autobot!” (I am admittedly a total mark for any rapper who rhymes “Robocop” with “Autobot,” I’m just honest.) And yet he sells lines like that, barking them out with the sort of mile-wide grin you can see just by listening to him. Even yelling “Turn up! Turn up! Turn up!” — the single most tired lyrical trope in all of 2014 rap — Casino sounds like what he’s saying matters to him, like he’s having fun saying it. It’s infectious. With his full-chested bellow, Casino now reminds me of ’90s proto-crunk demons like Magic and Hitman Sammy Sam and pre-Curren$y-association Fiend, using gonzo vigor to make up whatever he lacks in nuance. (If Casino manages to become Fiend to Gunplay’s Mystikal, he’ll have found his true calling.)

Frank Matthews also sounds better because the context of 2014 Atlanta rap is very different from what it was a year ago. Casino’s brother has proven to be a transformative figure, and even if his hitmaking has slowed a bit, his influence continues to spread. These days, Atlanta is full of giddy weirdos like deranged libertine Young Thug, an ascendent world-conqueror who shows up a couple of times here, magnetically purring and squeaking his way through “Communication” and “All This Money.” The other guests on Frank Matthews show the fuck up. Diamond, formerly of Crime Mob, does this devastating icy singsong on “Do What I Wanna Do,” showing that she no longer needs to get over on sass alone. Young Scooter, appearing a couple of times, continues to burnish his reputation as the trap-rap Eeyore, depressively moaning without skimping on ferocity. Lil Silk is so excited on “Regardless” that he can barely form words. And Future’s one appearance here, on “Pocket Watching,” is simply masterful, and it somehow has way more impact than all the accumulated verses on Ex Drug Dealer put together.

Still, Casino ably carries the whole thing himself, and some of the best songs are the ones with no guests. That’s because it’s fun to listen to his voice boom, but it’s also because he’s come a long way as a craftsman. His choruses have gained a certain stickiness. And he’s figured out how to make his verses fluid and dynamic, building up to raging climaxes rather than keeping the intensity at a steady level throughout. And if he’ll never catch up to his brother, he’s a whole lot closer to being something other than just Future’s brother now.

Download Frank Matthews here.