To create the video game “Six Days in Fallujah,” developers “tapped dozens of soldiers who were involved in the real-life 2004 battle for the Iraqi city to add realism to their action game, which the company plans to release next year. … As the capabilities of videogame hardware have burgeoned, the bar for realism in games has been raised. But Atomic Games wants its new release to be more than a game. The company sees it as a new kind of documentary.”