This might sound very stupid, but for some reason i think Necromancer Drones are actually polygons
Why do i think they are polygons? Because in Sandbox there is a glitch called "No More Polygons" where when the Necromancer collects squares, less shapes spawn. Which means Necromancer Drones might not be Drones, instead they might be Manipulated Polygons that follow the Necromancers Cursor. If this is not the case then they might be their own Ammunition.