Tropical Tidal Wave #36 from Nintendo Black Star Promos is a reverse holo promo card that currently sells for about $1,000 ungraded, with graded copies ranging from $810 at grade 9 to $3,970 at grade 10. A grade 10 copy sells for around $3,970, about 4× the $1,000 raw price, so high-grade copies are worth grading.