Activision Blizzard, the United States-based video games developer responsible for producing titles such as World of Warcraft and various Call of Duty titles, has stunned the mobile gaming world by announcing its acquisition of King Digital Entertainment. If that name sounds familiar to you, it should. King Digital is the company behind the mobile-gaming-phenomenon, Candy Crush Saga, as well as other popular titles such as Bubble Witch, and AlphaBetty Saga.