Young Thug has built intriguing partnerships with a handful of Atlanta's top producers, but soon after he first came onto the scene, his main guy behind the boards has been London on da Track. One need not hear "we got London on da Track" (which is actually said by Skooly, not Thug) to know it's a London track. His brand is a smooth and immersive sound, one that uses careful patterns to achieve a subtle hypnosis. 

A master pianist, London always begins a beat by building a melody. The drums and bass follow, providing the backbone, as well as the necessary trap connection, but the track's energy is most always driven by the keys. Thus, each melody is a singular mood created -- not by a sample or a programmed loop, but by London himself. And his compositions -- complex but rarely cluttered -- elicit rare flows and zany ideas from his closest collaborator. 

Though 2015 may have been Thugger's biggest year, the most important moment in his career is still the time he met Birdman, who took an immediate liking to the eccentric Atlanta slime. Thug, in turn, introduced Bird to Rich Homie Quan, and with their brilliant debut mixtape, the pair soon became synonymous with whatever Rich Gang actually was (is?). But they couldn't have done it without London, who, quietly in the background, produced a few of Tha Tour: Part 1's biggest tracks, including the one that came to define the entire movement, and for many fans, like myself, the entire summer of 2014: "Lifestyle." 

"So when I watch young'n work, London, kid got a different vibe...To me, right now, I think he's the best producer in the business," said Birdman in a promotional video released a month before Tha Tour: Part 1 that officially introduced the then 22-year-old producer. Later in the clip, while London's piano meanderings remain audible in the background, Thug echoes Bird's sentiments: "I fuck with a lot of producers, but I can honestly say nobody better than the n*gga." 

It's easy to see why both Bird and Thug offered such high praise. The first Rich Gang production London created (and one of his first real pay days) was "Hookah," on which Thug featured next to a then Cash Money artist, Tyga. The next month, June 2014, he was behind two hit records, "About the Money" and "Lifestyle," released two days apart. Three smash hits in two months, each making it onto Billboard, the highest-charting being "Lifestyle," which reached No. 16.  

Though his name will always be attached to that of his closest slime, he's extended his sound way beyond Thug and Atlanta. Within the past month, he crafted a piece of late-night magic for Jeremih and Ty Dolla $ign as well as a decidedly West Coast single that will appear on YG's next album. Many of us outsiders notice a rising Atlanta star one day and think he came out of nowhere, though that's rarely the case.