If you purchased your copy of the game in a box, you will need to download the Steam client from and once installed, go to the +Add a game link in the lower left-hand corner, and enter the product key from the back of the box. There are various ways to purchase Civilization V, but only one way to get hold of the SDK, and that is via Steam. Installing the Civilization V WorldBuilder The WorldBuilder tool is available free from Steam as part of the Civilization V SDK (software development kit), which also includes tools for modding units.
This is a powerful tool that allows you to configure everything from starting position, tech and relationships between Civilizations to how the game plays out, whether there is a limit on turns, and how Barbarians behave. This is made possible with the WorldBuilder software, which can be downloaded via Steam. If you’re bored already with the existing map options in Civilization V or are planning to setup and host your own multiplayer game, you might like to spend some time creating a custom map.
Build Worlds with the Civilization V SDK!
