A game including at least one level in which a player wagers a resource item to progress to a next-higher level or to receive an award. When the wagered resource item matches a resource item that has been randomly selected from a predetermined group of resource items, such progress or award is granted...http://www.google.de/patents/US6939229?utm_source=gb-gplus-sharePatent US6939229 - Gaming method, device, and system including adventure bonus game
