What name did Beyoncé use for her alter ego introduced around 2008?

Beyoncé used the alter ego name Sasha Fierce around 2008.

She described Sasha Fierce as a stage persona associated with confidence, sensuality, and a more aggressive performance style. The concept shaped her 2008 double album I Am... Sasha Fierce, whose two discs contrasted intimate ballads with high-energy songs.

The “I Am...” disc included songs such as “If I Were a Boy” and “Halo,” while the “Sasha Fierce” disc included “Single Ladies (Put a Ring on It)” and “Diva.” This division reflected the album’s central idea of separating Beyoncé’s private and public performing identities.

Beyoncé later said that she had retired the alter ego, explaining that she no longer needed a separate persona to access that confidence onstage. “Yoncé” is another nickname connected to her music, but it is not the alter ego named in the album title.