How do you balance -- and indeed encourage -- a war between factions without letting either side obliterate the other? How do you rule over gods, creatures, and men who refuse to obey you? How do you build a landscape of villages when bandits and mythology are conspiring to tear it down?
Open the Steam client, login and locate the Games tab on the top menu. Click this and then select “Activate a Product on Steam…”
Enter your unique code that's displayed on the 'Orders' page of CDKeys.com and follow the prompts to activate.
Your game is now viewable in the “Library” tab and is available to download/install when you’re ready. You can find additional support for the Steam client here: https://help.steampowered.com/en/wizard/HelpWithSteam