Cycling is a term used by players when they use or play a card that gives a +0 in terms of card advantage. Cards like "Upstart Goblin", "One Day of Peace", and "Into the Void" are all cycling cards. "Dark World Dealings" and "Dragged Down into the Grave" are not considered to be Cycling because they result in a -1 in terms of card advantage. Cards like "Royal Magical Library" can produce decks that have limitless cycling, by using cards that otherwise would shrink a player's hand.
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