Empyrean Empress Mouse
Much like her Sky Wardens, the Empyrean Empress is more of an absolute force of nature than a mouse. She is a perfect balance of the raw energies coalesced from the eight power types found within the Floating Islands. Her powers are so incomprehensibly vast that it is believed that she single-handedly built the Empyrean Sky Palace using nothing but sheer force of will.
Capturing her physical form is one of the greatest tests of strength and bravery for any mouse hunter but it is only a minor inconvenience for a being as mighty as the Empress. Her ethereal form is eternal and not tied to any singular existence which is what allows her to appear in all vaults within the Sky Palace simultaneously and perpetually.
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