Powerful upper body that kind of makes you want to conquer the land or something. I based this one off of the concept art above, but you'll all get to be the judges of how accurate it is or not. Been playing with this one for quite a bit, and thought I might share.
By the way, a small note for anyone using Ironfistking1313's Kain character build - the one I'm using in the screenshots, albeit a bit edited myself - you may want to adjust the Racemenu Bodymorphs of the 5.0 versions, and maybe even the main Elder Kain one. His build relies on mainly the original Skyrim body, and looks a little weird as is when paired with this body. Feel free to tool the sliders as you see fit in game.
Anyway, enjoy your conquest of the land.