On August 24, 2000, Microsoft published the expansion, "The Conquerors". It added new units and five new civilizations, including two Mesoamerican civilizations: the Maya and the Aztec. "The Age of Kings" was a bigger critical success than the first two games, with Game Rankings and Metacritic scores of 92%. Microsoft shipped out more than two million copies to retailers, and the game received numerous awards and accolades. Critics agreed that "The Conquerors" expanded well on "The Age of Kings", though issues of unbalanced gameplay were raised. "The Age of Kings" and "The Conquerors" won the 2000 and 2001 "Computer Strategy Game of the Year" awards from the Academy of Interactive Arts & Sciences, respectively.