The beat is witches brew, but beware this shit is potent

from Childish Gambino – Freaks and Geeks Lyrics on Rap Genius

Meaning

Witches brew is usually the basis for some type of potion or spell. CG’s verse is the equivalent of Ursula stealing Ariel’s voice. MEAN

“Witches Brew” is a brand of beer that is known for it’s “whopping” 9.3 alcohol content…so that shit is potent.

This could also be a reference to Miles Davis‘ jazz classic Bitches Brew, which could easily be censored as Witches Brew (e.g. to avoid cursing in public). Davis was a master of the trumpet and keyboard percussion instruments (xylophone, glockenspiel) which are the most prominent sounds on the beat for this song.

http://www.youtube.com/watch?v=FJk69zvgBhU

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