Dvorak is a card game where all the cards start out blank; players choose a theme, make up enough cards to get started, then continue to add new cards during the course of the game, provided that the other players approve of the cards. It can be played in two ways - either as a serious attempt to create a card game around a theme (a film, a book, a sport, or whatever you like), or a ruthless Nomic-style free-for-all, where each Player pursues his or her particular aims without regard for fairness or replayability.