Mike Caren got into the music business as a teenager, and his steady rise through its ranks was accelerated by his knack for writing huge hooks designed to jolt hip-hop tracks. He's helped pen multiple megahits for pop-rap titan Flo Rida, including the skronky “GDFR” and the pumping “Club Can't Handle Me.” And his flinty beat for Beyoncé's “Ring Off” added extra tension to B's lovers'-quarrel chronicle.