Telltale Games' video game version of the hit TV show and comic book The Walking Dead has spawned a sequel, called The Walking Dead: 400 Days and acting as a transition between the first and second "seasons" of the show, book and game. Unusually, the new game is available as a $5 in-app purchase from the existing Mac or iOS game. The Mac version is slated to be released today, July 3, while the iOS version will follow a week later. The game follows the story of five new survivors at a truck stop in Georgia.
