Cornerstone Mask Ogerpon ex #215 from Twilight Masquerade is a illustration_rare card that currently sells for about $13.40 ungraded, with graded copies ranging from $9.50 at grade 7 to $99.99 at grade 10. A grade 10 copy sells for around $99.99, about 7.5× the $13.40 raw price, so high-grade copies are worth grading.