So, at its core, magic is using a swarm of tiny (50-100 micrometers), naturally occuring robots to deliver substances to a given location and initiate chemical reactions that lead towards the desired result. It involves physics, chemistry, programing and communication.

So, how to prevent sieges from lasting until someone pulls out their fat man and obliterates the gatehouse, or the dragonborn from slaughtering 95% percent of the population with a magic sword?

Magic-denying fields that selectively nullify magic around a point of origin, of course. I think using the programing and communication aspects is the best for magic denial, as far as efficiency and universality is concerned.

However, micro machines receive their orders before they're fired and communicate between each other by holding hands (individual bots are spheres with several retractable arms with a gripper/hand at their end). A mage usually generates their own bots that recruit ambient ones, though one can rely solely on their own bots for a spell, if they're patient or strong enough.

Say, you summon me in the middle of the city, because you want to make a contract with me and become a magical girl. It's possible to fake the commands you direct at me after summoning, but if you summon me with the intention of walking up to the local jarl and banning him from life, that command is retained in the spell, that should be impenetrable to jamming attempts, thus no one on Earth could "talk me down" from slapping that jarl to death...

that is a problem!

Ideally, the communication of individual bots should be jammed, before they could form into my deadly, jarl-slapping avatar.

So, how could communication between individual bots be jammed? Note that the barrier isn't visible and doesn't have side-effects.


2 Answers 2


Overriding or conflicting commands being sent by other nanobots, or through coded light or electromagnetic signals.

The nanobots would naturally have some sort of "reset" switch or "master" command, or they couldn't be recruited into a new spell. Some sort of command telling them that the deed is done. Given the size and power levels of a single bot, they're unlikely to be equipped with very strong crypto to defend against hijacking.

So, they float through a barrier that flashes them all with the nanobot equivalent of "Ctrl-Alt-Del".

But this is probably too much, because while doable, it would be ruinously expensive - think of all the low-level spells that should not be affected by the barrier, on pains of having to recast them all over again.

Probably, then, the "barrier" would need to disrupt specific spells. It would need to be a more complex meta-spell in its own right, whose nanobots would first interface with the incoming spell, then "recognize" its purpose, allegiance or permission level, and finally if not satisfied they would try and unravel it, or if the worse came to worst, trigger a local-area total spell reset.

This would give rise to a arms race between attacking spellmasters and defense spellmasters, the latter trying to devise faster and more cunning "antivirus" or "firewall" spells, the former trying to camouflage their spells or subvert the magewalls.

  • $\begingroup$ What about the everything is forbidden, except what isn't strategy? $\endgroup$ Dec 29, 2019 at 0:25
  • 1
    $\begingroup$ @Mephistopheles the problem here is that "strategy" would become such only at a much higher level than the single nanobot. It would be like trying to build or modify the transistors in a CPU so that it couldn't run a word processor. There wouldn't be a "strategic" nanobot; probably there would be a generic signal "Assemble in numbers high enough to achieve suitable computing power" (the "beginning" of a spell), and a shared signal "Task completed, return to waiting state". In the middle, other signals to "be part" of the diffuse AI gestalt, send input, propagate output, perform calculations. $\endgroup$
    – LSerni
    Dec 29, 2019 at 18:11

Your nanobot thingamajics are basically a mechanical biological system akin to that of your body except it covers the world. It can converge and share energy, materials and information in order to cast magic. This also helps in keeping the swarm active and functioning.

The body doesnt want everything to be active at once, or wants to prevent certain actions from happening sometimes. To prevent this the body has ways to deactivate certain processes through various feedback loops. And this can be used for your nanobots.

Whoever designed it must have known that allowing all actions all the time is a bad thing, so sending it commands to specifically not do something like eat through the walls housing the fusion generator or the volatile chemical plant would be installed that cannot easily be overridden.


You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .