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.
Conspiracies aren’t legal for any sanctioned Constructed format, but may be included in other Limited formats, such as Cube Draft.
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.
A conspiracy’s static and triggered abilities function as long as that conspiracy is face-up in the command zone.
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.