Coming out at the same time as the most recent wave of Weapons Packs and Cyclops Variants was a sort of surprise new wave...the 'Micro Fleet.' Rather like the Star Wars sets which come with an off scale vehicle, pilot, and planet model, these include a micro scale Warthog, Halo 4 Master Chief, and a Mjolnir Helmet. A pretty neat idea, honestly.
The set itself is pretty simplistic. It includes a Rocket Warthog reduced to it's most elemental. It's about at 15mm scale, as it is quite comparable in size to the Halo Universe and Micro Ops lines released earlier by Mega Bloks and McFarlane's, respectively.
Also included is a little Forerunner tower. It's likely something from Halo 4, though it reminds me most of something from the original Halo: Combat Evolved.
Lastly, of course, we have the Master Chief. Nothing really new here, as this is the same sculpt as the earlier sets, including everyone's favorite the Cryo Lab. He also includes the Railgun, so if you didn't have a Halo 4 version of the Chief with Railgun, this is not a terrible way to get it.
The whole set stores completely in the Helmet, which has a hinged back plate.