Throughout Chance the Rapper's trippy new mixtape Acid Rap, you'll pick up on nostalgic samples of Slum Village, A Tribe Called Quest, Mary J. Blige, John Legend and even an ode to Kanye West's Freshmen Adjustment mixtape "Intro" on the two tracks "Good Ass Intro" and "Good Ass Outro." But Chance also admits that acid did contribute to the good vibes. "[There] was a lot of acid involved in Acid Rap," he tells MTV News. "I mean, it wasn't too much — I'd say it was about 30 to 40 percent acid ... more so 30 percent acid." So naturally, we had to ask: Was it difficult to rap under that influence? Hear him explain in the clip above.