Mimikyu ex #4 from Scarlet & Violet Black Star Promos is a reverse holo promo card that currently sells for about $2.29 ungraded, with graded copies ranging from $7.00 at grade 7 to $66.00 at grade 10. A grade 10 copy sells for around $66.00, about 29× the $2.29 raw price, so high-grade copies are worth grading.