Players may use plastic card sleeves or other protective devices on cards.
Often players will be using card sleeves to protect their cards from the dirt and friction they would otherwise be exposed to through repeated usage. Provided that they do not interfere with shuffling, or could be considered offensive, they will be allowed with the following conditions.
If a player chooses to use card sleeves, all sleeves must be identical and all cards in his or her deck must be placed in the sleeves in an identical manner.
Having decks of mixed brands/types/colors/condition/size etc. of sleeves is a no go, as it is allows players to tell their cards apart. Additionally the conditions of the sleeves should be noted. If most of the set is scuffed and worn on the visible side when in the deck, but a few sleeves are in notably better condition, the sleeves are not identical. Another common practice is to “double sleeve” a deck, in this case all cards must be double sleeved so there exist no variation in rigidity and thickness of cards in the deck. Notable deviations from the identical nature of the sleeves ought be considered Marked Cards.
If the sleeves feature holograms or other similar markings, cards must be inserted into the sleeves so these markings appear only on the faces of the cards.
So as to prevent information being revealed by reflecting the face of a card above in a stack all holograms and the like must be solely on the face of the card sleeve.
During a match, a player may request that a judge inspect an opponent’s card sleeves.
If a player finds something suspicious they may request a judge to check opponents sleeves for Marked Cards. The process for this is similar to that of a deck check, where the cards are briefly examined for dissimilarity or problems. It should be noted that all sleeves could be considered marked if examined closely enough, and this ought be considered when evaluating sleeves.
The judge may disallow the card sleeves if he or she believes they are marked, worn, or otherwise in a condition or of a design that interferes with shuffling or game play.
In the event that the card sleeves are determined to be interfering with game play or compromising the integrity of the game. The judge may require replacement sleeves to be used for the remainder of the tournament.
In the interest of efficiency, the judge may choose to delay any change of sleeves until the end of the match.
The act of requiring a player to change sleeves mid match is undeniably disruptive, if the judge feels that there is no urgent need, postponing the change of sleeves until after the match is a superior alternative. If necessary a time extension may be given to complete the task and allow the player to continue in the tournament.
Competitive and Professional Rules Enforcement Level tournaments impose additional restrictions on sleeves.
Due to the nature of Competitive and Professional Rules Enforcement Level events, additional restrictions are set in place to reduce the chance that the integrity of the event is upheld. As such in these events the following observations and regulations ought be enforced and considered.
Highly reflective backs are not allowed. Sleeves with hologram patterns across some or all of the sleeve front or back are not allowed.
If a sleeve has a highly reflective backing, information may be gained when picking up cards from the deck where some characteristics could be observed such as whether or not the card is a land, or what color it is. This of course is not something that can be allowed due to the risk it creates.
The restriction on hologram patterns across the front is in effort to maximize clarity of the game as to not disrupt the viewing of the card for both players. It should be noted that due to the insignificant nature of something like the Ultra Pro logo sticker, its placement and size make it a non-factor when evaluating the sleeves.
Sleeves with artwork on their backs may be subjected to additional scrutiny, especially if there is no solid border around the edges.
With solid borders a player cannot easily hide marks on the sleeves that can be seen when the cards are in a stack, whereas without a solid border, abnormalities are far harder to notice, and thus demand extra study when evaluating the sleeves.
When using sleeves on double-faced cards, sleeves must be completely opaque.
In the event that a player is using double-faced cards with in their deck rather than a checklist card, the sleeve must not allow any indication that a double-faced card is within. Often the easiest way to observe this is by looking at the back of the sleeve in various angles in light to determine opaqueness. If the sleeves prove ineffective at preventing the nature of the double-faced card from being revealed the player will either need to use appropriate checklist cards, or use new, suitable sleeves. The infraction Marked Cards may also apply.
The Head Judge is the final authority on what sleeves are allowed.