Empire Earth

Epochs are the ages a player passes through in Empire Earth. Each of these epochs represents an age within history. In Empire Earth, the last two ages (Digital and Nano Ages) are set into the moderate future. In the Art of Conquest, a third future age, the Space Age, is available. It deals with space colonization. Each epoch brings new technologies and units. Epoch advancement requires additional buildings to be built and the costs of advancing increases as more epochs are attained, although the ability to gather the required resources greatly increases as well.