The Rocket's Mewtwo (14 / 132) card can be found in the Gym Challenge Unlimited set.
Recently sold 17 times and based on those sales is worth around £60.00.
Currently, there are 12 open listings for this card on ebay.
This card sells in the range of £37.45 to £82.55, making it highly volatile.
This Rare Holo card was illustrated by Shin-ichi Yoshida.