Catan - Cities & Knights is an expansion pack. It creates knights to protect the land from invading barbarians and builds city improvements that confer benefits upon that city's owner, adding tactical complexity to the game and game length. First, there are 3 new commodities in the game distinct from resources. Second, the deck of development cards is replaced by three different decks, each corresponding to one of the commodities. Finally, players can also build knights on the island along their network of roads. These knights can be used to claim certain intersections but are also used to defend the island from periodic barbarian attacks. Get used to a tougher life on Catan and a longer but also more exciting game. The first player to reach 13 victory points is the winner. Must have the Settlers of Catan base game to use this expansion.