One Piece card sleeves

Size: standard, same as Magic and Pokémon

A One Piece card is a standard trading card, the 63.5 × 88.9 mm format sold as 66 × 91 mm standard-size sleeves. Ultimate Guard lists One Piece among the games its standard-size sleeves are for, alongside Magic, Pokémon, Lorcana and Flesh and Blood.

There is no One Piece specific sleeve size. Sleeves branded for the game are branded, not resized, and standard sleeves you already own from another game fit. What genuinely differs is the rules, and they are stricter than most players expect.

Opaque is a requirement, not a preference

Bandai's Tournament Rules Manual states that players must bring a tournament legal deck sleeved in opaque sleeves to constructed events, and repeats that cards should be sleeved in opaque sleeves. In most games opacity is advice; here it is the entry condition.

The manual also states that players must use sleeves to protect their cards during the course of a tournament, so as in Yu-Gi-Oh! and unlike Magic, sleeving is not optional at organised play.

The practical consequence is that clear sleeves are not a valid single-sleeve solution for One Piece. If you want a clear layer for the card's protection, it has to be the inner one, under an opaque outer sleeve.

Leader and DON!! cards must look different

This is the rule with no counterpart anywhere else in this niche, and it exists because of how One Piece is laid out. The Leader card sits in its own zone for the whole game and the DON!! deck is a separate stack of identical cards; neither is ever shuffled into the main deck.

The manual requires that Leader cards, as well as DON!! cards, be sleeved or unsleeved in a way that differentiates those cards from the main deck. So the usual instinct — one matching pack of sleeves for everything — produces an illegal setup.

Buy accordingly: one pack for the main deck, and a second, visibly different pack for the Leader and DON!! cards. The manual notes card loaders may be used for these, though judges may prohibit a loader they consider an obstruction to play.

The rest of the sleeve rules

All main deck sleeves must be identical and cards placed into them in the same direction and manner. Only one card per sleeve, and no other cards or printed materials inside a sleeve.

Players may use up to two sleeves per card to maintain card condition, sleeved identically across the deck. The manual adds a judgement clause worth knowing: if judges deem the type of sleeves used excessive, or that the sleeves allow cards to be distinguished from one another, a player may be instructed to change sleeves or remove them.

Sleeves with reflective backs or holographic fronts are not allowed, and sleeves must not obstruct the front of the card. Artwork on the backs is allowed provided all sleeves are identical and the artwork is non-offensive. Damaged cards — creased or bent — may not be used where the difference can be felt through a sleeve, which is a tactile test rather than a visual one.

Players can request that a judge check an opponent's sleeves during a match, and the head judge has final authority. As everywhere else, bring spares: the manual expects you to replace sleeves that become damaged or worn.