Our gunfire tore the machines apart, circuitry and hydraulic fluids sprayed out in patterns disturbingly-similar to blood. The special rounds we had were obviously working; you could see sparks and flickers as the metal filaments played merry hell with the electric components in their chassis. It was close, but we got all of the robotic workers down before they reached our barricade. But that wasn't the end of it. Impossibly, the shattered husks, destroyed microchips and frayed lines of fiber-optics jutting out in every direction, stood up and charged our line again.
They reached it this time.
Have you ever seen a robot tear into someone? One minute they're standing there firing their rifle, the next they're missing both their arms and have a new hole in their gut. It took three times before the 'bots went down permanently. It was like something out of a horror-movie nightmare.
We discovered magic in the universe that day, and God help me, I wish we never had.
So I had this odd idea: "What would a robot zombie look like?" Not in the visual sense, but in the metaphorical sense of its characteristics. We've all seen human zombies, we know their rough characteristics, and what makes them scary and disgusting. But what about a robot? One of the major aspects of undead creepy-factor is that a corpse isn't something that should be moving. The dead are dead, and they don't just get up and walk around.
But most people don't think of robots as being alive. So how can something that isn't nominally alive become undead? If it isn't "on", it's deactivated, and if it is "on", it's activated, and that's the way that things should be. How can you have that same horror effect with something that really doesn't have a distinct line between life and death? I think this is the biggest hurdle for the concept of an undead robot, and it's high enough that I don't think anyone else has really given it serious thought before.
The key to making it work, I believe, is to step back from the rawest edge of hardness in your scifi and expand the horizons of the universe. In recent years, we've made zombies into something that's actually got a veneer of plausibility, adding some pseudo-science here and there to make the idea of a reanimated corpse less full of magic and more reasonable to the modern mind. But since robots don't really have the same intrinsic alive/dead dichotomy that humans do, I think we should pull a page from fantasy and add some magic to the mix. We can recover that same sense of unnatural events by reanimating robots that every piece of engineering and robotics (and common sense) tells us should not be moving around
. Of course, this is much harder to do with robots than people, since most of us are less familiar with what makes for a truly disabling injury for a robot.
As a parting shot, perhaps none of this is needed in the first place? Is an undead machine really all that different from a pristine one that's hell-bent on destroying you? Both of them are insanely tough, and both are unlikely to stop without disabling levels of damage.
Further thoughts are appreciated.