Empire Earth: The Art of Conquest is the expansion pack for the real-time strategy game Empire Earth. Art of Conquest was published by Sierra Entertainment like with the original game, but was instead developed by Mad Doc Software. It was released on September 17, 2002, in the United States. The game was released in Europe later in the year, and the following year in Japan. The Gold Edition of Empire Earth, which features both the original and the expansion, was released on May 6, 2003. Art of Conquest added several new features to the original Empire Earth, including units, civilizations (Japan and Korea), civilization powers, and hero units. Art of Conquest also features three new campaigns: Ancient Rome, World War II, and 24th century Mars. The game received mixed reviews, averaging 66% on GameRankings. Gameplay The gameplay in Art of Conquest is the same as in the original Empire Earth, albeit with some changes. Variable difficulty has been added to those scenarios which had not received it in a patch of the original Empire Earth. Online multiplayer capabilities has been added, allowing players to play online with up to seven other players either over the Internet via a lobby system, or over a local area network (LAN). The new Space Age (Epoch XV) allows the building of spaceports and spaceships on maps that allow it. Robots replace Citizens in the Nano Age and infantry in the Space Age (these robots are known as Watchmen). Nano age Farms are run by robots, and by the Space Age farms no longer need citizens to manage them. Each civilization has its own power, or "Civ Power". Often, these powers are only available during certain epochs. A Civ Power gives each nation a specialty: the Chinese, for example, have the "just-in-time manufacturing" ability; while the Japanese have the "cyber ninja" ability. Empire Earth supports multiplayer over LAN connections and online. Multiplayer games are identical in form to single-player games. Art of Conquest multiplayer play has many exploits, which players can use to give themselves an unfair advantage. The game's publisher, Vivendi Games, has set up forums where players can report exploits. The multiplayer servers were taken offline on November 1, 2008; players are only able to play through local area network and Direct IP. Campaigns Three new campaigns were added in The Art of Conquest: an Ancient Roman campaign about Gaius Marius and Julius