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Term: Battle Cards in the KO Area Rulings
Several cards in this set cause battle cards to be put into the KO area. What does that mean?

Those cards are essentially out of the game, except if something specifically puts them somewhere else. They aren’t scrapped, so they won’t be reshuffled into your deck when your deck is empty.
Source: Wizards of the Coast (2019-11-08)    【Link to Ruling】
Tags: Battle Cards in the KO Area