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.
If you have a digital Xbox Play Anywhere title, you can play on both Windows 10 PC and Xbox One.
Little Kite
Play Anywhere games can be played on your PC and your Xbox. You will need to have installed the Windows 10 Anniversary Edition update on your PC, as well as the latest update on your Xbox One console. You only have to log into your Xbox Live/Microsoft account and your Xbox Play Anywhere games will be available to download. On your Xbox One, games will show as "Ready to Install" under "My Games and Apps". On your Windows 10 PC, games will appear in "My Library."
PC/Xbox Play Anywhere EUROPE
Localization restrictions applied. This product can be activated only in Europe.
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