The Core, referred to as The Night in the prophecy or Darcy while possessing Marcy Wu, is the main antagonist of the 2019 Disney animated series Amphibia.
It is a digital amalgamation of "Amphibia's greatest minds" and master of King Andrias that seeks to dismantle the prophecy that brought the girls to Amphibia. It's matrix has been uploaded into the body of one of the girls, Marcy, in order to further this goal.
While its main voice actor is currently unknown, as Darcy, it is voiced by Nolan Splavec.