Oft imitated but never equaled, the DJBooth Freestyle Series ran from February 2009 through June 2011. Its 250 total entries came courtesy of a veritable who’s-who of underground and emerging emcees, including rising stars like Kendrick Lamar, Wiz Khalifa and Mac Miller. Now, it’s back for a second round. Following on the heels of reader-acclaimed contributions from ANTHM, Rich Quick and Clyde Shankle, the latest installment comes courtesy of Isaac Castor, the Michigan buzzmaker who brought us Heisenberg back in early October. On High Art Flow, the emcee gets his lyrical Picasso on over eerie, sampled boardwork by Hippie Sabotage. The rapper formerly known as Gameboi is currently hard at work on his High Art LP, which as yet lacks a drop date. Keep it locked for release details on the set, as well as all the latest tunes.