Tournament rule 421.8
When two or more cards are recycled to the player’s Main Deck as part of a single action, the above procedures 1-7 should be followed for that group of cards to properly randomize them before recycling them.
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When two or more cards are recycled to the player’s Main Deck as part of a single action, the above procedures 1-7 should be followed for that group of cards to properly randomize them before recycling them.