Nekrostethics

William open and closed his fist, each finger following his will with a in a jerky, twitching fashion. It was an unusual feeling to have ones limbs move by thought alone. Whenever his mind wandered, the hand wiggle and move unbidden. Still, he thought as he willed it to close around the rifle, it was better than no arm at all. Not by much, but enough.

A recent and controversial development in the field of necromancy and necroengineering, Nekrostethics are undead limbs attached to living people to replace one they've lost. The dead limbs are never bound to the recipient, but attached to metal or wooden pegs, then bound and wired to the person. It isn't wholly theirs, controlled through will and thought rather than nerve and muscles. A small cluster of undead brainmatter is tucked away in or on the limb, sometimes swelling out like a bloated infection, and that is what allows the limb to function.
Like all undead, the Nekrostethics are powered by electricity and must be recharged every now and then, usually through a socket implanted straight into the dead meat. More expensive variants are usually adorned with wood, brass, or other material to mask their grotesque appearance. The very rich often pay for the freshest replacement, hewn right from another living human, which can sometimes pass for living tissue if maintained well.
Still crudely mechanical, Nekrostethics function best when at the size of a leg or arm, and can at their smallest be a hand. The smaller they are, the less motor function they exhibit.

Like any other dead, magic-infused matter, Nekrostethics are vulnerable to infection by Rotbloom Fungi.

by Unsplash