Jost performance as stone cold is just that a performance …he is acting… this is not an act to " pul off" either you have or you don't.
One other actor off the radar here is Jonathan Scafe …his performance as Sydney Snow, the cold blooded pistolero in Life is A Mystery /Bleeding Kansas in Hell on Wheels ..

Anson Mount ( of AMC Hell On Wheels ) has the blue steely eyes and the quite brooding to pull this off… a man of few words whose expressions are deep .