Mew-EX #XY126 from XY Black Star Promos is a reverse holo promo card that currently sells for about $160 ungraded, with graded copies ranging from $215 at grade 7 to $8,500 at grade 10. TCGrader's AI has graded 7 copies of Mew-EX (XY Black Star Promos), averaging 8.4 overall. Only 29% scored 9 or higher, so genuinely mint copies of this card are scarce. A grade 10 copy sells for around $8,500, about 53× the $160 raw price, so high-grade copies are worth grading.