Premise: A small insect-like robot, the Reanimator sweeps the battlefield in search of casualties and corpses it can graft to. By means of robust surgical instrumentation and a set of specialized pithing needles, it integrates itself with the central nervous system of its victim, effectively reanimating it via sophisticated electrical currents and impulses. Once successfully done, it will search for, and equip appropriate weaponry, assisting its alien masters with the newly hijacked body. Though it prioritizes grafting over combat, it will defend itself, or create grafting opportunities with a light integrated particle beam weapon/electrolaser. Once its current host is rendered 'inoperable' it will merely detach itself and systemically go about seeking another (assuming it survives). Area of effect/EMP weaponry, and substantial overkill are the most reliable methods of destroying them when they are attached to a host body.