Once per turn, during either player's turn, when your opponent activates a card effect, you can negate that activation, and if you do, destroy it.
This unique feature has made it one of the most coveted Mewtwo cards ever released
3 AZs Tranquility (Special Art Rare) $50.00 AZ's Tranquility claims the crown as the most valuable trainer in Ninja Spinner, as this mountain of a man captured our hearts in Pokemon X & Y before shattering them again in Pokemon Legends: Z-A
As promised in a previous thread, I purchased a several different packs of sleeves to do a rough comparison
See also: Binder layout planner What are the chase cards in Rumble? The top chase card in Rumble is Lucario (Promo) at $2999.19
He was the first leader to be featured, and he certainly wont be the last