Rocket's Mewtwo is card #14 of 132 in Gym Challenge (2000), a Rare Holo illustrated by Shin-ichi Yoshida. At about $433 it is the #4 most valuable card in the set. In a Gym Challenge booster it turns up about once every 59 packs. It is one of 89 Mewtwo cards printed so far.
1999Base Set
2000Gym Challenge
2003Ruby & Sapphire
2006Holon Phantoms
2009Pokémon Rumble
2015BREAKthrough
2019Unified Minds
2023Crown Zenith

















See the full Gym Challenge card list
An ungraded Rocket's Mewtwo from Gym Challenge sells for about $433. A PSA 10 is worth more, roughly $5,634 by our estimate, and a PSA 9 around $1,733.
It is a Rare Holo, and it shows up about once every 59 Gym Challenge packs.
Shin-ichi Yoshida drew the art for this card.
Yes, as a digital simulator. Holobrook lets you open Gym Challenge booster packs in your browser with the set's real pull rates and keep what you pull in a digital binder. No real cards, nothing to buy.