Sicko Mobb brothers Lil Ceno and Lil Trav are among a handful of west-side rappers creating a niche sound made specifically for the dance style known as bopping, and they're doing a hell of a job at it; when I went to a Wala Cam War Zone dance battle in Austin a couple weeks ago, the duo's intoxicating mix of high-pitched synth melodies and Auto-Tune-soaked vocals sent nearly every teen in sight into bopping frenzies. (If I recall correctly, Sicko Mobb's "Young Heavy" was the only song that got played more than once that evening.) Sicko Mobb just dropped a couple tracks with heavy-hitting Chicago rappers: "Bitches & Bikinis" with Twista and "Maserati" with Lil Durk. On "Maserati" all three MCs turn out quicksilver-paced performances to match a sunny beat that's ever so slightly jittery thanks to an adrenaline boost—even Cicero on da Beat's producer tag is sped up to sound like a chipmunk recorded the beat maker's stamp. As Complex magazine scribe David Drake points out, Durk also references the bop shout-out Rick Ross dropped on Jay Z's "Fuckwithmeyouknowigotit," which further extends the life of an otherwise unexceptional tune from Magna Carta . . . Holy Grail. "Maserati" is today's 12 O'Clock Track, so take a listen to that number and "Bitches & Bikinis" below.