6 Accelgor is an Efficient Single-Prize Attacker First Printing: Journey Together Some cards have the unique ability to attack the opponent, then run away to the bench so that they can safely attack the opponent on the next turn, which can make them incredibly frustrating to deal with
Leonardo is the perfect way to cheat expensive artifacts into play, and gives you a built-in win condition by buffing those Thopter tokens massively if you can swing in with a full hand
In the midst of a fairly stale format, its Pok-Body Keystone Seal instantly divided the overall metagame into speed decks and Trainer lock decks
There's also the tiny problem of this costing seven mana, all of it colored, but the combination of both winning the long game and keeping you alive to see it makes seven feel cheap, and there's enough behind this card that there is no need to worry about following it up with another copy unless your opponent can fire one back at you
Dark Machamp may be under the control of Team Rocket, but there's no telling what unique versions you may find