Well similar to the unique mini-covenant discovered in an early episode of Spartan Ops. ForgeWorldMaps has discovered 2 separate game types that allow you to be either an Oversize giant Spartan or a miniature Spartan. Unfortunately it appears that you can only have one or the other, as there is no game file that has both currently (but who knows).
So if you want to have a good laugh or make some interesting videos in Halo 4. Here’s the preview and where to download the gametype file.
– Chief Landless