Cornerstone Mask Ogerpon ex #160 from Prismatic Evolutions is a holo illustration_rare card that currently sells for about $15.77 ungraded, with graded copies ranging from $15.00 at grade 7 to $64.69 at grade 10. A grade 10 copy sells for around $64.69, about 4.1× the $15.77 raw price, so high-grade copies are worth grading.