Proxy card

A proxy card is an easily acquired or home-made substitute for a collectible card. A proxy is used when a collectible card game player does not own a card, and it would be impractical for such purposes to acquire the card. This usually occurs when a player desires a card that is cost-prohibitive, or is "playtesting" with many possible cards. When doing intensive training for a competitive tournament, it often makes more sense to use proxy cards while figuring out which cards will be brought to the tournament. Another card is substituted and serves the same function during gameplay as the actual card would.

A proxy can also be used in cases where a player owns a very valuable card, but does not wish to damage it by using it in actual play.

Proxy cards can be used in various situations. The rules and restrictions are object of common agreement, or a given policy, and may differ from the above-mentioned "fair play requirements".

Famous cards that are often proxied are the so-called power nine in Magic: The Gathering, which are considered totally out of balance in gameplay, while being unaffordable for the average player, due to their rarity and enormous price on the secondary market.

Players who do not trust each other blindly will usually agree on common rules, defining which kind and number of proxies, if any, is allowed for each player. These rules may vary drastically depending on the participants and the occasion. However, some restrictions are implied naturally by common sense and plain physics.

The main issue to guarantee fair play in a card game is that all cards in the deck must be indistinguishable for any player who does not view the front side (if card sleeves are used, the term 'card' means the sleeve with the card inside). Ideally, all cards should be indistinguishable in the following characteristics to effectively prevent cheating.

Besides these physical implications, it should be considered that someone (the players or a judge) will need to control the validity of the cards - which may prove difficult with some of the above points.

Therefore, the use of proxies is sometimes further constrained to only one method of fabrication, for instance.

The difficulties of control can also be an argument to totally prohibit the use of proxy cards.

Once the front of a proxy is revealed to the other players, it must be clear to everyone what it is meant to substitute. The decisions of what a player's proxies are meant to substitute must be made before starting play. If two proxies are meant to substitute different cards, they must be easily distinguishable by looking at their front side. Ideally, the label of a proxy should be enough to tell what it's meant to substitute. Alternatively, a legend or agreement can be used to prohibit players from changing these mappings during play.

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Wikipedia