This is gorgeous. I love the composition as a whole, but it's the little details that take us on a short trip to the world of the Archives. The simplicity of the line work as well as the rough hewn edges are just icing on the cake for me. You provide just enough detail to communicate to me where I am, and who I'm with, without making my eyes tired of the detail.
Those intense black shadows just tell of such a punishing heat that I hope for the subject's sake his armor sports some form of cooling system.
I would like to see more trigger discipline in a soldier though.