Flygon #25 from Nintendo Black Star Promos is a reverse holo promo card that currently sells for about $3.20 ungraded, with graded copies ranging from $15.20 at grade 9 to $67.75 at grade 10. A grade 10 copy sells for around $67.75, about 21× the $3.20 raw price, so high-grade copies are worth grading.