The Flygon (25 / 40) card can be found in the Nintendo Black Star Promos set.
Recently sold 1 times and based on those sales is worth around £40.49.
Currently, there are 3 open listings for this card on ebay.
This card sells in the range of £40.49 to £40.49, making it very stable.
This Promo card was illustrated by Kouki Saitou.