Rayquaza #XY64 from XY Black Star Promos is a reverse holo promo card that currently sells for about $15.93 ungraded, with graded copies ranging from $39.87 at grade 7 to $580 at grade 10. A grade 10 copy sells for around $580, about 36× the $15.93 raw price, so high-grade copies are worth grading.