Master Chief Returns
The main character of the first three games in the Halo franchise is finally making his return to the series, after several off-shoots of the franchise have been created, including Halo Wars, Halo 3: ODST, and Halo: Reach.
Halo 4 was announced at the national E3 gaming and technology convention, where a teaser announcement video was played. Cortana, his AI, was also presented in the video. It has been speculated that he will fighting against the Forerunners, who are the ancient creators (possibly machine beings) of the Halo Rings, which are what the Chief had been working to destroy in all three of the first games.