Mosaic is an action selection game. On your turn, you will perform one of seven actions and acquire components.
Acquiring Components is important in creating the unique mosaic of your civilization. They are used as prerequisites for many new technologies, as well as for scoring. Also, by pursuing specialization in one or more Civilization Components, you may be able to claim a "Golden Age" of that type.
As the game goes on and your Civilization grows, scoring cards are eventually revealed from the four decks. Each time a scoring card is revealed, your Civilization will score for each region that you dominate with your cities and military units. After the third scoring card is revealed, there is one final turn and the game ends. You will then score for your cities and towns, your wonders, projects, and golden ages, and for all of your cards that score for your unique Civilization Components.