315.1 Conspiracy cards are used only in limited play, particularly in the Conspiracy Draft variant (see rule 905). Conspiracy cards aren’t used in constructed play.
315.2 At the start of a game, before decks are shuffled, each player may put any number of conspiracy cards from their sideboard into the command zone. Conspiracy cards with hidden agenda are put into the command zone face down. (See rule 702.106, “Hidden Agenda.”)
315.3 Conspiracy cards remain in the command zone throughout the game. They’re not permanents. They can’t be cast or included in a deck. If a conspiracy card would leave the command zone, it remains in the command zone. Conspiracy cards that aren’t in the game can’t be brought into the game.
315.5 Conspiracy cards may have any number of static or triggered abilities. As long as a conspiracy card is face up in the command zone, its static abilities affect the game, and its triggered abilities may trigger.
315.6 The owner of a conspiracy card is the player who put it into the command zone at the start of the game. The controller of a conspiracy card is its owner.