Sid Meier's Civilization 2

Building on the foundations laid by the first Civilization game in 1991, Sid Meier's Civilization II made a number of meaningful improvements to presentation and gameplay. For starters, Civilization II was the first game in the series to employ the now-familiar isometric camera perspective and provide the freedom of a map editor. 

Civilization II also introduced new strategic considerations via diplomacy ratings, alliances, espionage, and an expanded arsenal of combat units with distinct firepower ratings and hit points. Leading any of 23 civilizations, players could incorporate units ranging from archers and elephants to AEGIS cruisers and stealth fighters into their armies. 

In addition to assembling and commanding a military, players made every critical social, economic, and political decision as they attempted to build an empire to span history. After founding their first cities in 4000 BC, players had until the year 2020 to achieve victory by conquering all rival civilizations, being the first to build a spaceship that reaches Alpha Centauri, or scoring more points than any other civilization.

The options to create your own maps and to download maps created by other players ensured that no two games of Civilization II ever needed to be alike, and still more longevity came courtesy of two expansions released in 1996 and 1997.