The Zapdos ex (33 / 40) card can be found in the Nintendo Black Star Promos set.
Recently sold 2 times and based on those sales is worth around £21.54.
Currently, there are 2 open listings for this card on ebay.
This card sells in the range of £16.72 to £26.36, making it stable.
This Promo card was illustrated by K. Hoshiba.
The fact that it is a EX card makes it one of the more valuable cards.