Giratina #XY184 from XY Black Star Promos is a reverse holo promo card that currently sells for about $8.30 ungraded, with graded copies ranging from $8.73 at grade 7 to $389 at grade 10. A grade 10 copy sells for around $389, about 47× the $8.30 raw price, so high-grade copies are worth grading.