So, to be clear, another player's 'restriction' card effect counts as 'a cost or requirement' that prevents an action from being announced?
How come Peace and other card search effects get a specific exception?
Limited: Search your Dynasty deck for a non-Unique Holding. Bring it into play (bowed), paying all costs.
A player is not assumed to know the face-down contents of his or her decks, for purposes of the Good Faith Rule.
Example: An action’s effect tells the player to search his or her deck and bring a card from it into play. If there is no legal card to play left in the deck, the player still may take the action in good faith.
What if there is a legal card left to play but the player has no unbowed gold and no 0 cost holdings?
The player may choose to have a search fail; he or she need not retrieve a suitable card even if found.
If an effect directs a player to search for a card and do something with it (such as play it or put it into the hand), and that thing fails, the card is discarded instead.
Wouldn't choosing to have the search fail make announcing peace violate the good faith rule, since it involves putting a card into play as a non-optional effect? Wouldn't failure to put the holding searched for by peace into play (due to inability to pay, other player's card effect (bad kharma a one koku), whatever) be a violation of good faith?