This set of cards replaces the dice in The Settlers of Catan and offers various events influencing the game.
The deck consists of 36 dice cards to represent the 36 different combinations that can be rolled with 2 dice. This means that number "rolls" are evenly distributed according to its probability. The deck also represents the roll of one die (for use with the Cities and Knights Expansion).
To add an element of randomness to the dice deck, a New Year card is added on top of the bottom 5 cards. When this card is flipped, the deck is immediately shuffled again so 5 cards will not be used.
Regarding the events: sixteen cards do not have an associated event, the six "7" cards of course are associated to the "Robber Attack" event, and the rest of events only appear once (six events) or twice (4 events).
Note this is an expansion, and you require base game to play. Select "Settlers of Catan", under Product Details, to view games and expansions in this series.