Serperior #BW20 from BW Black Star Promos is a holo promo card that currently sells for about $4.07 ungraded, with graded copies ranging from $19.24 at grade 7 to $96.00 at grade 10. A grade 10 copy sells for around $96.00, about 24× the $4.07 raw price, so high-grade copies are worth grading.