Compare prices for purchasing Sid Meier's Civilization: Beyond Earth Exoplanets Map Pack PC, whether it's in physical form at a store or in digital version as a CD key.
If you do not have a Steam account, you will need to download the client from the official website, install it and then create your account. Once you are logged into your account, click on "Add game" in the bottom left corner and then on "Activate product on Steam". After a few clicks on "Next", you can finally enter your CD key, the game will automatically be added to your library and the download will begin.
answering the message of 