Card advantage

Card advantage (often abbreviated CA) is a term used in collectible card game strategy to indicate one player having access to more cards than another player, usually by drawing more cards through in-game effects. The concept was first described early in the evolution of Magic: The Gathering strategy, where many early decks relied on a player drawing more cards than their opponent, and then using this advantage to play more cards and advance their position faster than their opponent. By 2007 it was recognized as one of the most important indicators of who is ahead in a game and has been utilized in the development of strategy for nearly every collectible card game created.

The basic concept of card advantage is one player having more cards in hand and/or in play than their opponent. Card advantage is generally indicated in terms of a positive number: if a player casts Ancestral Recall, a spell that causes a player to draw 3 cards, that player is said to have gained +2 card advantage. In this scenario he has gained three cards (the ones that were drawn) and spent one card to do so (the Ancestral Recall itself).

Card advantage is often also the result of making a play where your own cards are used to neutralise or eliminate a greater number of your opponent's cards. This form of card advantage is often stated in terms of X-for-Y, where X and Y are respectively the number of cards of the player and the opponent. If X is bigger it expresses card advantage, and if Y is bigger it expresses card disadvantage; i.e. a 3-for-1 is a positive advantage, a 1-for-2 is not. Example: If in a game of Magic a player plays Day of Judgment, a card which destroys all creatures in play, when they themselves have no creatures in play and their opponent has two creatures in play, they are said to have gotten a "2-for-1", where 2 indicates the number of opposing cards removed from play and 1 indicates the card spent in order to accomplish this outcome.

It is seen as a baseline to spend one card to get rid of one opposing card; this is often referred to as trading (not to be confused with the actual bargaining/trading of cards outside of a game). A player who "trades" one card of their own for two of their opponent's is often gaining a long-term advantage as their opponent will run out of cards before they do.

Card advantage is typically generated in four ways.

Other means of one player getting ahead on cards exist. For instance, if one player attacks with a Hill Giant, and the other player blocks with a Grizzly Bears, the Grizzly Bears will die and the Hill Giant will survive. If the defending player then casts Shock on the Hill Giant, they will have traded two cards of their own (the Grizzly Bears and the Shock) for one card of their opponent's (the Hill Giant), putting their opponent ahead in terms of card advantage.

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