The Imperial Age in Age of Empires III is the fifth and final age of the game. It is an important era, because researching the technologies available in this age will usually determine the difference between victory and defeat, thus breaking a long game.
Though the Imperial Age is very expensive, it is useful, because of all of the technological improvements are desirable and massive which can also make the player's civilization almost unstoppable. To advance to the Imperial Age the player must have 4000 Food and 4000 Coin .
All Home City Cards that deliver troops that have already been used, can be sent again after reaching Imperial Age.
Units and Buildings that become available in the Imperial Age