At this point, who hasn't had too many drinks and tried rapping over that amazing flute beat? Of course, when Chance and King Louie did it, it actually ended up sounding pretty damn good. An official cover with his full band needs to happen. This is great. Watch fan-shot footage as well as a video taken on stage by Chance himself below.
Watch Chance The Rapper's "Mask Off" Freestyle With King Louie