The ultimate Painkiller package – a motley collection of crazy guns, levels and enemies – contains the titles ""Painkiller"", ""Painkiller - Battle out of Hell"", ""Painkiller - Overdose"", as well as the latest add-on ""Painkiller Resurrection"". Each Painkiller offers unusual, fast-paced shooter fare with extravagant settings and a healthy dose of madness and horror.
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