You are part of an elite commando force that must infiltrate a hostile alien cite. Once inside, you must scour industrial landscapes, crawl through waterways and air ducts, navigate treacherous canyons teeming with vicious mutants, stow away on an alien spacecraft, and destroy the enemy's secret moon base.
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
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