Along with her album, Beyonce has presented her fans to a new alter-ego named Sasha Fierce. The singer affirms that this new persona is the fun, more sexual and more aggressive side of her. This is, however, the “general public” version of the story. The esoteric meaning revealed by the symbols surrounding this new persona is much deeper: Sasha Fierce is a symbolic representation of an artist taken over by evil to obtain success.

“I have someone else that takes over when it’s time for me to work and when I’m on stage, this alter ego that I’ve created that kind of protects me and who I really am”.
-Beyonce

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https://vigilantcitizen.com/musicbusiness/beyonce-to-sasha-fierce-symolic-occult-rebirth/