When attempting to explain the situation with Varis and Solus to my sister, who just saw the 4.0 ending credits, this just now hit me.
Why does Solus look like Emet-Selch? We know that Solus was possessed at an early age, and that many clones of Solus were made so that Emet could just possess a new one whenever the body died.
But why does Solus, who was at one time a normal person, look like Emet-Selch?
Are there any examples of an ascian transforming the appearance of their vessel? I can't think of any off the top of my head.. So I don't think this could be explained as a case of Emet rearranging Solus' face to suit him (also assume that would be very suspicious to the people Solus knew in life before his possession).