Released on 6 May 2003.
Art of Conquest added several new features to the original Empire Earth, including new units, new civilizations (Japan and Korea), civilization powers, and new hero units. Art of Conquest also features three new campaigns: Ancient Rome, World War II, and 24th Century Mars.

Empire Earth: The Art of Conquest includes three new single-player campaigns set in ancient Rome, the Pacific Theater of World War II, and Asia in the 24th century. In addition, each of the 21 pre-designed civilizations in the game gains a unique special power, building, or unit. Examples include: the Kingdom of Italy's Metallurgy power, which allows them to pay building costs with gold or iron interchangeably, Great Britain's S.A.S. unit will be able to plant demolitions and swim across water, and the United States' market building will allow that civilization to trade abundant resources for scarce ones.

Players can become the greatest conqueror of all time by creating, building, and leading a civilization to transcend the ages - from the discovery of fire, to flight, to the next frontier: space.
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