Greninja-GX #SM197 from SM Black Star Promos is a reverse holo promo card that currently sells for about $18.75 ungraded, with graded copies ranging from $17.49 at grade 7 to $500 at grade 10. A grade 10 copy sells for around $500, about 27× the $18.75 raw price, so high-grade copies are worth grading.