Cornerstone Mask Ogerpon ex #215 from Twilight Masquerade is a holo illustration_rare card that currently sells for about $10.94 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 9.1× the $10.94 raw price, so high-grade copies are worth grading.