used to create Empire Earth—later released under the name Titan 2.0—was retained and upgraded for Empires. Significantly more detail was added to the units' 3D models than had appeared in Empire Earth. Further additions included reflection mapping, environmental bump mapping and a new physics engine. According to Goodman, reusing the game engine enabled the team to place its full concentration on gameplay, without worrying about technological development. Another priority was storytelling, an element of the RTS game Warcraft III: Reign of Chaos (2002) particularly enjoyed by the Empires team. Empires was designed primarily for multiplayer gameplay: the multiplayer development team created and fine-tuned each civilization, which the single-player team then used in campaign levels. Because the civilizations do not overlap, Bishop considered game balance to be the most difficult aspect of the project. Previously, Stainless Steel had balanced its games in a microcosmic fashion: the "individual components" of each civilization—for example, the economic power of Germany versus that of England—were balanced against one another. Balance on this scale led to overarching balance. However, this technique hinged on a broad similarity between civilizations that is not present in Empires. Consequently, the company had to abandon its earlier practice and "develop an entirely new methodology", Goodman explained. The result was a macrocosmic system of balance, in which civilizations are inherently unbalanced but equally powerful overall. As with Empire Earth, each new build of Empires was given to "strike teams" of playtesters. By April, between six and eight months of playtesting had been performed by a group of six professional RTS players. GameSpy's Allen Rausch wrote that the process allows a game to be "consistently tested, evaluated, balanced, and tweaked" at every stage of development, which enables complex forms of balance. This let the Empires team create a looser version of the rock paper scissors system typical of RTS games, wherein one type of unit is either very strong or very weak against other types. In Empires, each unit's strengths and weaknesses were made subtle enough to curb "hopeless mismatches" and reward skillful micromanagement, according to Bishop. The duration of the average battle was increased to provide more opportunities to micromanage units. Empires went gold on October 7, 2003, and it was released on the 22nd of that month. Reception Empires was received positively by critics, according to review aggregators Metacritic and GameRankings. The game's sales, when combined with those of Empire Earth,