(sometimes referred to as Hand Looping) in which a card takes cards out of the opponent's hand and either shuffles it into the deck or sends it to the Graveyard (or occasionally Banishes it)
That makes it well worth it to crack a pack and see if you get a big hit
It doesn't copy whether it's tapped or untapped, whether it has any counters on it or Auras and Equipment attached to it, or any non-copy effects that have changed its power, toughness, types, color, and so on
Being able to draw the cards you need without repercussion, in a game system devoid of any casting costs or required material costs, is game-breaking
That brings it down to Amazons best-ever price (as confirmed with price tracker camelcamelcamel )
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