The Shaymin EX (77A / 108) card can be found in the Roaring Skies set.
Recently sold 6 times and based on those sales is worth around £34.04.
Currently, there are 8 open listings for this card on ebay.
This card sells in the range of £28.32 to £39.76, making it quite stable.
This Rare Holo Ex card was illustrated by TOKIYA.
The fact that it is a EX card makes it one of the more valuable cards.