Over the course of Atlanta’s recent A3C Hip-Hop festival, Grooveshark teamed with Stankonia Studios and the Royal Flush/SMKA production team for an exclusive mixtape. Stankonia Sessions: A3C Edition features 9th Wonder, Killer Mike, Ying Yang Twins, Rapsody, Freeway, Thurzday and many more. Check out “Knockin’ On Heaven’s Door” below and the mixtape in its entirety on November 16th.