From the box: 'How many countries in the European Union can you name? The problem here is that only one person in the group knows the topic, so how arrogant will you be in your prediction, and will someone challenge you?' Players take it in turns to secretly draw a category card from the stack. They then bid how many things in that category - whether it's 'vegetables' or 'film stars' - they can name. Bidding continues around the table, with the other players unaware of what they are actually bidding to name, until one player decides not to bid, and challenges the preceding player. The category is then revealed to all players, and the challenged person must name at least as many things as they bid. If they succeed they keep the card; otherwise the challenging player claims the card, gaining a point.