Just thought I'd share a link to some Halo 4 armor stuff I had the privelege
of working on. The image below is my concept of the Locus Helmet with an optional variant skin that comes with it if you pre-order from Mighty Ape, as well as some other goodies.
You can see more stuff here, most of which I worked on along with Albert Ng and Robo Gabo: http://halo.xbox.com/blogs/Headlines/post/2012/05/30/The-Halo-Bulletin-53012.aspx