If rap has a Thelonious Monk, it’s Kool Keith: find the beat, work with the beat, but then flout the beat and the meter and the boundaries of A/B rhymes so thoroughly it leaves the Ultramags’ peers sounding basic. Ced-Gee killed it on the mic, too, but his contributions to chop-heavy sample-based production — teamed up with the gone-too-soon engineer/beat creator Paul C. (“Give the Drummer Some”) — completed a genre-reinventing epiphany that his rhyme partner envisioned.