Challenge your imagination as you battle the mightiest villains in an exciting, action-filled adventure through GOTHAM CITY™, METROPOLIS™, ATLANTIS™ and other iconic locales from the DC Comics Universe. Bring out your inner super hero (or villain!) with the all-new Hero Creator by crafting completely original objects out of parts of existing DC Comics characters. Then assign unique properties to your creations and use them to solve puzzles, or share them online with friends – which they can use in game or further modify as they like.Go to: http://store.steampowered.com/ and download STEAM client
Click “Install Steam” (from the upper right corner)
Install and start application, login with your Account name and Password (create one if you don’t have).
Please follow these instructions to activate a new retail purchase on Steam:
Launch Steam and log into your Steam account.
Click the Games Menu.
Choose Activate a Product on Steam…
Follow the onscreen instructions to complete the process.
After successful code verification go to the “MY GAMES” tab and start downloading.