Microsoft’s Gamescom conference has just wrapped up with 343 Industries introducing a new game to proceedings in the form on Halo Wars 2. It is scheduled to release in 2016 for both Xbox One and Windows 10, with Creative Assembly helping with development. A brief cinematic trailer was shown as a soldier is dragged by an ally away from enemies. He fires at them until running out of bullets.
There was no gameplay on show but I expect more will be shown soon.
Source: MS Gamescom conference.