"Card Restrictions" (カードの使用制限Kādo no Shiyō Seigen, literally "Card Usage Restrictions") refers to a set of rules that prevent the specific use of cards in official tournaments. These rules can be different between the different languages of the game. The main reason for those adjustments is because those cards are excessively used by many fighters, promoting less variety in decks.
There are different terms to refer to the restricted cards.
: If you want to have a group of cards in your deck, neither of them cannot be included in the same deck. For example, you may have four copies of card A and zero copies of card B, but you cannot have three copies of card A and one copy of card B, in order to meet this criteria.
: You may only have up to one single copy of that card in your deck.
: You cannot choose that card as your first vanguard at the beginning of the fight.
: The card cannot be included in any deck at all.
: The card is no longer part of the Card Restrictions.
: The card has two of the mentioned restrictions simultaneously.