It's been developed in tandem with external developer Certain Affinity, which has worked on several pieces of Halo content for Microsoft in the past.
The expansion contains 3 new maps designed for up-close-and-personal gameplay, best suited to small teams. The maps are titled Landfall, Monolith and Skyline.
There are 10 new achievements, if you're into that sort of thing – that's 250 points.
The new maps will also be integrated into existing Infinity Slayer, Capture the Flag, SWAT, Regicide, Doubles, Team Objective and Team Throwdown playlists. DLC maps will appear in a playlist if all members of the match have the content purchased or the War Games Map Pass, Microsoft said.
The Majestic expansion will set you back 800 Microsoft Points, but if you picked up either the Halo 4 Limited Edition or Halo 4 War Games Map Pass, you'll automatically get access.