Civilitation 4

Civilization IV is a turn-based 4X game, in which the player leads a civilization from a small tribe to conquering the world over several millenia. Conquest can be done in at least four ways: diplomatically being declared the world's leader, using military to defeat all other civilizations, becoming technologically superior to the other players, or to win through expansion of the civilization's culture across the world. Additionally, the game scores each civilization based on a number of factors, and victory can be had if the player's civilization score far exceeds any other, or if at the end of a limited-turn game, the player has the highest score. The game can be played as a single player facing against one or more computer-controlled opponents, or through online multiplayer games alongside computer opponents.

Link download Civilization IV [full version]