It costs 3, which is great, its +1 is better than it looks, its -1 has a plethora of uses, and the ultimate ability creates the sort of chaos that's simple, fun, and memorable, as opposed to the chaos from cards like Possibility StormPossibility Storm and ScrambleverseScrambleverse
Every time it attacks the opposing player, they lose a card from their hand and every time the enemy attacks Houndoom, they lose another card
For commons and low-value rares, I like to price them in lots instead of one by one
Mewtwo's universal popularity across every generation of Pokemon fan is the primary driver of this card's sustained value
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Knight " " CXyz Simon the Great Moral Leader " " CXyz Skypalace Babylon " " Dark Rebellion Xyz Dragon " " Dark Rebellion Xyz Dragon, Four Heavenly Dragons " " Dark Requiem Xyz Dragon " " Endless Bond " " Full-Armored Xyz " " Odd-Eyes Rebellion Xyz Dragon " " Pendulum Xyz " " Reincarnation Unveiling Mail " " Resurgam Xyz " " Unbreakable Xyz Barrier " " Wonder Xyz " " Xyz Agent " " Xyz Align " " Xyz Armor Fortress " " Xyz Armor Torpedo " " Xyz Avenger " " Xyz Bento " " Xyz Block " " Xyz Burst " " Xyz Change Tactics " " Xyz Dimension Splash " " Xyz Double Back " " Xyz Effect " " Xyz Encore " " Xyz Energy " " Xyz Entrust " " Xyz Force " " Xyz Gift " " Xyz Import " " Xyz Lay " " Xyz Override " " Xyz Poseidon Splash " " Xyz Reborn " " Xyz Reception " " Xyz Reflect " " Xyz Remora " " Xyz Revenge " " Xyz Revenge Shuffle " " Xyz Reversal " " Xyz Revive Splash " " Xyz Shift " " Xyz Slidolphin " " Xyz Soul " " Xyz Territory " " Xyz Tribalrivals "