Sideboarding

After a game concludes, players may move cards between their Main Deck, Material Deck, and Sideboard (as long as the new decks follow format conventions). Sideboards are collections of cards that are extraneous to the starting main deck and material deck which serve as cards that may be accessed and included in main decks and/or material decks after the first game in a match. Sideboard restrictions and criteria are dependent upon the tournament format type.

Before a game starts, players must present their face-down sideboard to their opponents. Opponents can count the number of cards in a player’s sideboard at any time but players are never required to discuss the amount of cards they have added or exchanged from their sideboard to their main and/or material decks.

For constructed formats, the combined number of copies of a card within the main deck and sideboard cannot exceed 4 total copies unless otherwise specified by the card. Similarly, the combined number of copies of a champion or regalia card among those in the material deck and sideboard cannot exceed 1 copy. Cards moved to and from the material deck to the sideboard and vice versa can only be done in such a way that deck-building constraints are not transgressed. All deck restrictions and format conventions for deck construction must be met after sideboarding is completed. If sideboarding results in illegal deck constructions, this can be penalized by judges by an issued game loss.

Players may access and look at their sideboard at any point in time between games and rounds. For constructed events, the starting main decks, material decks, and sideboard must be reverted to their starting compositions as described in the decklist registration; any sideboarding must be undone and reverted to the pre-sideboarding state after a match is concluded.

Players may only sideboard cards to and from their main decks and material decks after each game in a series after the first game of a match is played, regardless of whether or not an intentional draw is made or if a game loss is issued before the first game is played.

E.g., In a match starting with a record of 1-0 for Player A before the first game is played, both players must still play a first game before sideboarding.

Sideboarding is considered concluded after both players have presented a sufficiently shuffled deck to their opponent for final shuffle/cut). Players may not continue sideboarding or change their sideboarding decisions after a shuffled deck is presented an opponent.