Hanabi (2-5 players, about 30 minutes, ages 8+, published in the US by R&R games)is a co-operative card game that is nominally about fireworks, but is really about communication and knowing the limits of one's own understanding. It won the Spiel de Jahres (tabletop gaming's equivalent of the Oscar) in 2013.
Players take on the role of Japanese pyrotechnicians with a shed full of unlabeled fireworks that they must assemble correctly before the show begins. This translates to working together to make five stacks on the table of cards numbered 1-5 in each of the five suits.
The catch is that everyone holds their own hand of cards backwards, so you can't see yours but everyone else can. On your turn you can play a card (but 3 misplays ends the game), discard a card (but some cards aren't disposable), or give another player a hint about what they have.
The hints are very limited, though, both in number (you get only eight of them, and replenish them mostly by discarding) and in what you can say — you can tell someone which of their cards are a certain color or a certain number. A flaw in many co-operative games is that the most skilled player can take over and dictate everyone else's move, but in Hanabi that's impossible, because nobody has proper information about what the best move is.
Mathematically, there aren't enough cards in the deck to provide enough hints through discards to give everyone the whole story about their hands. This means that players have to judge each others' intentions when they hint — "She told me I have three red cards; does that mean I can discard them all, that I should play one right now, or perhaps that one of the cards she didn't name is the undiscardable yellow five I don't see in anyone else's hand?"
When played with two the game changes significantly from other player counts, as the players need to negotiate another layer of when and how to switch roles between hint-giver and card-player. More than one couple I've introduced the game to has found this to be a great "spouse game" for this reason.
The game is fast to teach, immediately enjoyable for new players, and extremely replayable. At first, this game is very hard to win, but the dead-simple scoring lets you know at a glance how close you got and encourages just one more play in the very best way. The box also includes a sixth suit of cards that can be used in a number of ways to make the game even harder, but after dozens of plays I don't think I'll be touching them any time soon.
Over a number of games, groups develop a language about what certain hints mean, and this language formation is both how you win the game consistently, and the place where play transcends into politics. Being good at Hanabi requires a theory of mind that accepts that your own understanding has limitations. That despite the fact that communication has ambiguity; striving for clarity and making use of context are desirable things. That sometimes you don't get to be the hero or to do everything that you want in order to ultimately achieve your collective goals.
If this game replaced Uno as the funny-deck-of-cards-game in every home in America, we might finally get our collective act together in terms of empathy, communication, ambiguity, and knowing our own limitations, instead of seeing the naked aggression of a Wild Draw Four as the answer to life's problems.
