So in a nutshell, the 500 years old sword mentioned by
@Paul_Frank is referring to Shiki’s broken antique sword from KnK.
It loses mystery from being broken.
No I meant this
A fantastic race.
As it sounds, they are beings that exist only in fantasy.
Demihumans like sprites and giants.
Demonic beasts like demons and dragons.
As their very existence is a "divine mystery", it is said that they themselves surpass magic.
It is the law that a divine mystery will be eliminated by a greater divine mystery.
As magic stored its power in knowledge,
the fantastic races store their power in their long lifespan.
Even if one masters magic as a human, that is only about the last five hundred years.
For those who have lived since ancient times, a five hundred year old divine mystery is not even worthy competition.
It's about how the mystery of magic only goes back like 500 years most of the time in terms of mystery, so high enough level stuff (being from the ancient times), just can't be affected by it.
Which would be..? I see general claims about Spiriton Hacking lacking mystery, but I don't remember any basis for that claim in the games (or novels, now that Strange aknowledged it).
Spiriton hacking lacking mystery, I assume, comes from the fact that by 2030 its just widespread technology, not some thing only select few magi use because it's useless like in current times. That would just cause it to have no mystery, its not directly stated because by 2030, no one really uses any sort of magecraft anymore so no one would talk in terms of mystery.
As for what I was referring to, in KnK Touko comments on magic being nearly dead in general, and explains mages and such and how they work, ending by saying that without mystery, magecraft and mages would weaken, they wouldn't go away, as they just become mundane methods of things. So they still exist, just without mystery despite being magical.
Case Files also mentions Shugendo just not caring about mystery, now yes, that doesn't necessarily mean that it has none already, but it implies that like the case with the mundane stuff Touko mentioned, it'd still work even without it, just weaker.
Mystery isn't disqualified as soon as a single individual human becomes aware of something's function, it's specifically noted that scientists hoarding knowledge in ancient times allowed things to retain mystery, I believe it was in Lord El-Meloi.
I never said it is? Humanity in Nasu just knows a lot, or believes certain things don't exist, hence so few things having mystery.
And what do you mean "unknowable"? We know for a fact that most Mysteries can be learned fully by science as time goes by, which is why even True Magic could be downgraded into Magecraft once science goes far enough. Hell, we're even told the materialisation of the soul is required for space colonisation, aren't we?
I mean it has to be unknowable within the bounds of what science has advanced to at that point. That's been shown as what gives large amounts of mystery, as opposed to just being unknown (as in, the amount of mystery that'd actually get you the ability to affect stuff like servants). Using the example of true magic you brought up, they're 5 things that can't be understood with science and replicated in other ways as of now, hence them having more mystery.
As for the space colonization thing, no I don't think we are told that, as space colonization occurs without it, and is possible without it.
See, this is also something I see going around a lot, but how can that be rationalized with Magic Resistance being a skill?
I mean the easy explanation for how MR is still a skill despite this, is just that the MR skill is for things that have enough mystery to affect them. We know it isn't just the MR skill that grants their immunity, given the whole thing about Medea (a caster without the skill) being able to beat any modern mage up to and including like, Ciel, Touko and Aoko for instance. We also see during the fight with Rin that even while playing around, the second Rin even tried to attack using magic, Caster just nullified it without a spell of her own or anything, it just stopped in front of her and disappeared. It's further stated that for Ciel to win, she'd need like, the 7th scripture, which conveniently is something that has enough mystery.
It's like with Wuzhiqi and Lugh, they have so much mystery that they can ignore the majority of modern magecraft (in Lugh's case actually all of it) but things with more or equal mystery do exist and thus get to affect them. For Lugh its Mr "Strongest Type Moon Protagonist", for Wuzhiqi, whatever they were using to keep her busy while Waver gave the pep talk to Ergo. It'd be the same case with servants, they're divine mysteries and thus even people without MR are untouchable to the majority of mages, not all though.
In fact, Servants are noted as being Ghost Liners, the greatest type of familiar, on par in terms of mystery, with Elementals, Nature, Animal, and Guardian Spirits, etc, and those do in fact just like, generally negate most modern stuff.
They're also supposed to be on par with the majority of the 27 DAA minus like, ORT and the obvious outliers. The majority of them are old enough to resist the majority of modern stuff as well (some reaching like, 2k years old) which would mean servants can as well.
So it's pretty evident all together that the MR skill sorta just functions as something which negates the remaining stuff that doesn't get stopped by the mystery gap, with its own levels after that, eventually making the user immune to all magic in the modern day as opposed to just a lot of it. And even if that argument isn't satisfactory for whatever reason, there's so much stuff showing that a certain level of mystery shuts down most magecraft and then saying servants are at that exact level either way.
Also, I'm 99% sure it's noted MR doesn't even do anything against raw magic beams, just spells.
Also yes, it does work on just beams, that's the entire reason Astolfo with the book could bring Sieg to the Gardens despite being blasted with beams of energy, it raised his MR.
Their immunity is more provided to them being spiritual entities. As soon as they become materialized by the grail mud, items with magical energy can kill them also
That's the case even without being materialized, strong enough magical objects (which would mean it has enough mystery too) can harm one. And what the line about materialized servants eaten by Sakura actually says, is that strong enough Thaumaturgical Instruments can bypass their shadows, not even kill them, just bypass their protection.
But all in all that's not really the main point here. The main point, at least as brought up by me and Crimson and whoever else, is that verse equal by the rules just like, can't give mystery to people. It'd be granting powers and a power system to people for the sake of a match, which isn't what it's for, as seen with the Destiny examples I mentioned where you aren't allowed to do that. It's just meant to make equivalent energy systems count as the same for the purpose of things working or not working (i.e genjutsu working outside of Naruto cause of the Chakra stuff)
The amount of mystery granted by certain things just doesn't really matter if no one gains that benefit outside of the verse.
