Advantageous Proclamation

• WWizards of the Coast2014-05-29
  Official Ruling
  The effect of Advantageous Proclamation is cumulative. If you have two in your command zone to start the game, your minimum deck size is reduced by ten, and so on.
• WWizards of the Coast2014-05-29
  Official Ruling
  In Limited formats (including Conspiracy Draft), the minimum deck size is generally 40 cards. With Advantageous Proclamation, your Conspiracy Draft deck must contain at least 35 cards.
• WWizards of the Coast2016-08-23
  Official Ruling
  You can look at any player's face-up conspiracies at any time. You'll also know how many face-down conspiracies a player has in the command zone, although you won't know what they are.
• WWizards of the Coast2016-08-23
  Official Ruling
  You don't have to play with any conspiracy you draft. However, you have only one opportunity to put conspiracies into the command zone, as the game begins. You can't put conspiracies into the command zone after this point.
• WWizards of the Coast2016-08-23
  Official Ruling
  Conspiracies are colorless, have no mana cost, and can't be cast as spells.
• WWizards of the Coast2016-08-23
  Official Ruling
  A conspiracy's static and triggered abilities function as long as that conspiracy is face-up in the command zone.
• WWizards of the Coast2016-08-23
  Official Ruling
  A conspiracy doesn't count as a card in your deck for purposes of meeting minimum deck size requirements. (In most drafts, the minimum deck size is 40 cards.)
• WWizards of the Coast2016-08-23
  Official Ruling
  Conspiracies are never put into your deck. Instead, you put any number of conspiracies from your card pool into the command zone as the game begins. These conspiracies are face up unless they have hidden agenda, in which case they begin the game face down.
• WWizards of the Coast2016-08-23
  Official Ruling
  Conspiracies aren't legal for any sanctioned Constructed format, but may be included in other Limited formats, such as Cube Draft.

Rulings via Scryfall