Young Thug and Future are often mentioned in the same breath. It’s not just because they’re both Atlanta rappers, or that their creative arcs began cresting at the same time, but because it’s hard not to spot some obvious stylistic parallels, the most glaring being Auto-Tune. It’s hard to believe that the two ridiculously prolific MCs—who grew up 20 minutes from each other, run in the same circles, and dip their pens in the same lean-laced ink—so rarely cross paths. Both rappers are longtime running mates of producer Metro Boomin. They frequent the same track lists: Travis Scott’s Rodeo, Chance the Rapper’s Coloring Book, Lil Durk’s LilDurk2X, Mike WiLL’s Ransom 2, to name just a handful of the albums they’ve featured on. Thug once claimed Future was planning to sign him to the Freebandz imprint for $1.5 million, but the deal never came to fruition. For a while, everyone seemed to be putting the two together—except the artists themselves.

Their weird dance quickly shifted from “constant coexistence” to “outright avoidance” in 2015 when Metro publicly questioned the productivity of other rappers and warned that they shouldn’t try to replicate his and Future’s tireless work rate. Thug took offense, and called Future the Tito to his Michael Jackson. Months later, as both artists were preparing to drop new projects, Future and Thug traded insults about output (“I hope Apple save you lil niggas… Or church!!!!”). It seemed these two pillars of the rap zeitgeist would never connect as fans hoped. Things turned around when Thug apologized for the “internet arguments,” making amends on stage during Drake’s Summer Sixteen tour and finally hitting the studio. Thug named a song on JEFFERY “Future Swag,” and more recently featured Future on the BTG number “Relationship.”

Capping their tumultuous dynamic, Future and Young Thug join forces for a new mixtape called Super Slimey and finally find common ground—in syrupy Auto-Tune, colorful diamonds, Patek Philippe timepieces, double cups, cruise ships, and personal torment. But maybe it’s because they’ve squabbled so much about efficiency, and quality over quantity, that Super Slimey is somewhat anticlimactic. It is, in part, a release memorializing audio engineer Seth Firkins, who died in his sleep last month. Firkins was Future’s primary vocal producer and mixer, a man behind the scenes on several popular mixtapes, Future's reissued debut Pluto 3D, and 2015’s Dirty Sprite 2. (The engineer also worked on records for Jay-Z, Rihanna, and Young Thug.) Firkins worked closely with Future for more than six years, and so Super Slimey is offered as an homage. “Super Slime in Peace Seth Firkins,” Future tweeted after the project dropped. On “4 da Gang,” he raps, “Go check my profile, I beat the verdict/I was kicking it in overdrive, for Seth Firkins.” These guys value the studio grind most, and so the highest compliment they can pay him is to keep working.

Future often finds strength in tribute and on Super Slimey, he pushes through the pain just like on 56 Nights, when he toasted his newly-freed, wrongfully-detained DJ Esco. Few go bigger than Future in mourning, and Thug also adds his share of colorful one-liners and wowing stunts (“Different color diamonds, I’m a peacock,” “I’ve been blown a mil’ on jewelry, but it’s past tense”). There are flashes of their more private sides, too, like Thug rapping, “It’s true I said I love you but I didn’t promise” on “Real Love,” or Future opening up about depression on “4 da Gang”: “I look my demon in the face, I’m booted up the worst way… I can’t grieve, ‘cause ain’t none of my grandma bills late.”

Neither Future nor Thug is at the peak of his powers on Super Slimey, which forgoes explosiveness and poignancy for streamlined action, and many of the solo cuts shine brighter than the team-ups. The same problem plagued Future’s collaboration with Drake, What a Time to Be Alive. The assumption here was always that this would be different because Future and Thug supposedly occupy the same territory—they’re both croon-first, spontaneous emoters whose viscous squawks rely heavily on pitch-shifting technology to add dimension—but there have always been subtle variations in the ways they like to move in open space, and their short track record shows they have trouble maximizing their talents in tandem. Most of the songs are never greater than the sum of their parts. Even when the verses and hooks aren’t pedestrian (by their standards), the segments seem cut together. A song like “All da Smoke” is really just a FUTURE cut with a pasted-in Thug verse. But there are moments like the Offset-assisted “Patek Water” or “200” where the stars align and they seem like perfect companions, or at least sparring partners. Even when they don’t click, you sometimes end up with two dynamic MCs trying to dunk on each other.

The Super Slimey production crew spotlights standout beatmakers from across the Future and Young Thug discographies: Mike WiLL Made-It, Southside, TM88, Wheezy, and London on Da Track. But Metro Boomin, who has unquestionably had a hand in both artists’ success and produced their best ever tag-team cut “Chanel Vintage,” is noticeably absent from the project. That void is never quite filled, despite the constant slaps, delivered especially on the glimmering Thug solo song “Cruise Ship” and the spectral “Drip On Me.” There’s something unfulfilling about Metro unwittingly driving a wedge between them and not being around for their reunion, as his comments seem to reverberate throughout it. If anything, Super Slimey is a reminder that compromise isn’t always productive.