Yes, KORE is a Scrabble word!

Letter values in Scrabble US: K 5, O 1, R 1, E 1.

Is it a valid word?

KORE is a valid word in the official Scrabble dictionary (US), the UK Scrabble Dictionary and Words with Friends (ENABLE).

(Greek mythology) daughter of Zeus and Demeter; made queen of the underworld by Pluto in ancient mythology; identified with Roman Proserpina

Not playable in Scrabble US: PERSEPHONE, DESPOINA, CORA.