Nightling

The Nightlings is not a separate race of living beings, but rather are living beings that was infused by Nightwater resulting in changes in their psyche and physical bodies. The Nightwater will enhance their muscles, skin, their entire bodies to be as hard as steel, and give them strength up to 10 times the average of their kind can.
To assimilate a living being to turn it into a Nightling, they will have to use a machine called the Ebon Assimilator which will infuse as much of their bodies with Nightwater in the shortest time possible. Mistakes in this process can result into the body rejecting the infused body parts, or the other way around.
When Nightlings are exposed to electromagnetic radiation the affected cells are unable to replicate. This is perhaps due to the reason that Nightwater can only be created in the absence of electromagnetic radiation and that Nightling cells require Nightwater to be built. 
Nightlings have no sex drive, their entire being and lust is only for their nation. Their bodies require much more nutrients than normal to survive. It is believed that the reason for this is because of the Nightwater reinforcing their entire bodies being a semi-living being itself that requires sustenance to replicate alongside their cells. 
Because of the Nightwater in their blood, flesh, and bones, Nightlings are loyal to their nation to an extreme degree. It is to the level where they are willing to sacrifice all they have and their individuality to serve their country, though it seems that this loyalty is only for the community they were raised in, which allows other nations to raise loyal Nightlings of their own. Though disloyal Nightlings do exist, it is usually because of their different perception of what is considered serving their nation.