The Necrotic Short Sword is a blade found within a secured armoury, marked out from its fellows by its power to deal necrotic damage. Of its own appearance nothing was set down; yet that necrotic nature argues some tie to dark or forbidden energies.
The sword came to light amongst a store of other arms — spears and crossbows and the like — once the armoury had been unlocked. It carried an unsettling aura, a hint of malevolent influence or curse, though no ill effect showed itself upon the handling of it. The party chose to keep the Necrotic Short Sword for its possible worth and its singular properties.