What celebrity voices are imitated by the crystal beasts?

You are likely referring to the Crystal Gems from the animated series Steven Universe.

The Crystal Gems do not imitate celebrity voices, but they each have their own unique and recognizable voices.

Here's a breakdown of the main Gems and their voice actors:

* Steven Universe: Zach Callison

* Garnet: Estelle

* Amethyst: Michaela Dietz

* Pearl: Deedee Magno Hall

While they don't imitate celebrities, they do sometimes put on voices or accents for comedic effect.

If you are thinking of another show or media where the characters imitate celebrity voices, please provide more information.