Mahouka [LN/M] - Character Speculation/Theories: Tatsuya

[mrSh4dy]

Originally Posted by Echizen777

Tatsuya's Regrowth is more of a superpower. I don't understand what you say by vacuum, it doesn't matter where she is because magic is used by linking to the Information Dimension and in the information dimension, the Eidos of everything are printed there. Eidos is an information body so as long as you exist in the material world you have Eidos, even non living things have Eidos.

The details about Regrowth were explained in details in Volume 7 by Miyuki

Spoiler for Miyuki-sensei:

"How long will Tatsuya-kun's magic last?"

Using magic to heal was only a temporary measure. That was the basic rule of healing magic.

By constantly recasting the magic during its effective period and repeatedly cheating the world, this was the only way to finally stabilize the illusion of healing in the actual world.

If the effective time was short, then a fresh application of healing was immediately necessary.

"It's perpetual."

However, her answer was completely unexpected.

"There is no need for recasts like conventional healing magic."

Miyuki's response encompassed all of Mari's concerns and was voiced specifically for Isori and Kirihara to hear.

"There is no restriction in motion. They are able to completely function as normal."

"Is such a thing possible?"

Mari wore a skeptical expression at this reply.

"You don't believe me."

"It's not that I don't believe you..."

Mari wasn't the only who couldn't comprehend this.

"I am very thankful that he saved Kei... But I've never heard of healing magic that results in complete healing after one cast. This runs counter to the basic laws of healing magic. Is he really healed? Does that even qualify as healing magic? What the hell did Shiba-kun do!?"

"Kanon-chan, calm down."

Mayumi gently coaxed Kanon to rein in her excitement.

"Miyuki-chan, please don't think poorly of her, OK? Kanon-chan is just really worried about Isori."

Hearing Mayumi's interjection, Miyuki smiled slightly in response.

"Still, I am very intrigued by exactly what he did. Since this isn't healing magic, what exactly..."

"Mari! Inquiring about other people's magic is forbidden!"

Just when the atmosphere turned a little congenial, Mari's statement immediately disrupted the balance and prompted a severe warning from Mayumi.

"Thank you, Saegusa-senpai. However, I think it's fine."

Yet Miyuki expressed her gratitude towards Mayumi's concerns but also mentioned that there was no need to worry on their behalf.

"I believe that it's only natural to think I would mind. Nonetheless, if it's only to explain this to everyone here, I think Onii-sama wouldn't object."

This was also a subtle hint to keep this to themselves. If they could not keep this a secret, then this would be as far as the conversation proceeded.

"I'll keep my mouth shut."

"I won't tell anyone."

With that, both Mari and Kanon replied in this manner.

The other members also swore likewise.

"I will keep anything I heard confidential, even towards Nakura."

In the end, even Mayumi spoke up.

"Oh, it's hardly anything that outrageous..."

Miyuki revealed a rare, wry smile.

No matter how Mayumi swore to keep her secrets, in the end, this would still flow into the ears of the Saegusa Family.

Even then, Miyuki judged that this would be OK.

At the end of the day, it's not like anyone could replicate this anyway.

"The magic that Onii-sama used was not healing magic."

Sitting in an upright posture, Miyuki quietly began.

This way, even the listeners reflected her posture.

"The name of the magic is 'Regrowth'. Changes in the Eidos can be rewound up to 24 hours in the past, copying and rewriting the Eidos from before any damages or harm from external sources were incurred, then using Magic Sequences to rewrite the current Eidos. The rewritten target will adhere to the updated information and restore itself to before any harm was suffered."

Miyuki paused for a moment after saying this and looked over everyone else.

"Now that I mention it, does everyone know why the effects of magic are only temporary?"

After asking the question, Miyuki continued without giving anyone a chance to respond.

"The effects of magic are not eternal because the restorative powers of Eidos are at work. The restorative power of the Eidos tries to revert itself to before any external alterations occurred. However, the rewritten Eidos from 'Regrowth' is only the target's own information from before. If you're being rewritten by your own Eidos, there is no need to revert to the time of injury and will remain in this world in a state where the injury never happened. All of this becomes as if nothing had ever happened."

Mari and Kanon exchanged a glance.

Mayumi blinked several times.

Isori's body went stiff and Kirihara wore a gobsmacked expression.

There were all sorts of expressions, but the sentiment being expressed was all the same.

"...Then, Tatsuya can heal any injury in one try, is that it? That's almost impossible to believe. Even for Tatsuya, this is..."

Mikihiko was the one who verbalized his internal monologue.

"Not in one try, Yoshida-kun."

Miyuki smiled and denied his words.

"It's practically instantaneous. In addition, the target is not restricted to biological organisms. Onii-sama can restore anything, regardless of whether it's the human body or a piece of machinery."

The conventional rules of magic don't apply here.

Originally Posted by amtro

The Eidos is not magical energy. The eidos are the information structures of all things in mahouka, if you control the Eidos then you control everything. This is why Tatsuya's abilities are so damn potent, because he can make the Eidos do what he wants it to (within the scope of his BS abilities) without having to suffer from the reversion power that everyone else has to deal with.
If Tatsuya cannot reverse energy into matter then he can simply draw it from the restorative powers of the eidos.

That still doesn't explain where he get's the material from.

Eidos are the data of the world and they form the core of that what we see (I got that mixed up earlier).
Now normal mahouka magic is about making changes to the Eidos while the natural balance in the world eventually reverts this back to normal. This is because the data can not be changed externally, but because Tatsuya ability uses the already established data to reform itself it won't be overwritten.
I get that, however what is used to recreate that arm. The human body exists as data in the Information Dimension but in the corporeal world it exists as

Elements in the Human Body
Element Percent by Mass
Oxygen 65
Carbon 18
Hydrogen 10
Nitrogen 3
Calcium 1.5
Phosphorus 1.2
Potassium 0.2
Sulfur 0.2
Chlorine 0.2
Sodium 0.1
Magnesium 0.05
Iron, Cobalt, Copper, Zinc, Iodine
Selenium, Fluorine

Now my problem is where do the elements come from to restore that arm.
-If he cuts of his arm does he regrow it and have 2?
But what did he use to reconstruct his new arm with the 1st one still around?
-If he cuts of his arm does he somewhat partially rewind time which reattaches his arm?
Considering the speed and how it is described this doesn't fit.

This is where I'm lost as to what he actually does.

[amtro]

You do realize that he can just fuse sufficient hydrogen atoms to create the other atoms, right?
Regardless, the conversion of energy to mass is a theoretically sound phenomenon.

[Navinor]

Really guys, i do not understand why some people want Tatsuya to be weak, or even dislike him like hell.

1. I like the way Tatsuyas Character is build. He is strong from the beginning. He is not an emo character who is always crying, only to become rambo in the end.

Tatsuya is a more realistic character than this rambo heroes or the "funny heroes" (Ise-> Highschool DxD)

Tatsuyas developing has no limits. Because we know still nearly NOTHING about his TRUE powers.

I do not understand people who want to make him weak. He is already very strong because he HAD his "Ganbate" phase already.

With his 17 Years he is a walking, living weapon of mass destruction.

BUT, there is always a problem with that.

He is cold, he has nearly no feelings and yes he is manipulative.

Do you remember Code Geas, Lelouche? He was nearly the same, only with feelings. (Mostly hate)

And what happened in the end to him? Right he died. (The normal way, to end great series in japan)

Tatsuya is build as nearly the same "archetype" of character. And we have an Japanese author.

The light novel will get 25 Chapters and NO INCEST ENDING. That was comfirmed by a contract
from the publisher with the author.

So i think for the guys who do no like Tatsuya. Mosty likely he will die. Oh yes he will get his ultimate "Bad Ass" moment, but after that, he will admit that he is an
"incomplete human" and will sacrifice himself to the greater good.

Because this is a japanese Light novel, with a japanese writer and with japanese way of thinking.

And the most important thing for japanese is to sacrifice themselfes for the greater good.

So calm down guys, i do not think he will survive chapter 25

[Echizen777]

Originally Posted by mrSh4dy

Now my problem is where do the elements come from to restore that arm.
-If he cuts of his arm does he regrow it and have 2?
But what did he use to reconstruct his new arm with the 1st one still around?
-If he cuts of his arm does he somewhat partially rewind time which reattaches his arm?
Considering the speed and how it is described this doesn't fit.

This is where I'm lost as to what he actually does.

His arm will reattach almost instantly once it's cut due to the speed but if he willfully suppresses it another one will be created. It copies his Eidos from the past in the ID and the information is pasted on his physical body. His Restoration in the animation depicted it well IMO. Time is rewinded only in the Information Dimension.

Against Lina it was not cut but was disintegrated, it will be the same. But if he had been in this state for more than 24 hours he would have kept one arm forever.

Originally Posted by Navinor

Tatsuyas developing has no limits. Because we know still nearly NOTHING about his TRUE powers.

Are you trolling or something? What power of Tatsuya is unknown?

[Navinor]

Originally Posted by Echizen777

His arm will reattach almost instantly once it's cut due to the speed but if he willfully suppresses it another one will be created. It copies his Eidos from the past in the ID and the information is pasted on his physical body. His Restoration in the animation depicted it well IMO. Time is rewinded only in the Information Dimension.

Against Lina it was not cut but was disintegrated, it will be the same. But if he had been in this state for more than 24 hours he would have kept one arm forever.



Are you trolling or something? What power of Tatsuya is unknown?

Are you agressive or something?

He has still limiters on him? Tons of them? And we do not know EVERYTHING about him. A lot of time till CH 25 to get more information.

[Echizen777]

Originally Posted by Navinor

Are you agressive or something?

He has still limiters on him? Tons of them? And we do not know EVERYTHING about him. A lot of time till CH 25 to get more information.

I am not saying that we know everything about him but to say that we don't know his true powers is exaggerated. We know all his techniques, Miyuki is the limiter who can affect his powers to various levels, he was at full power in Vol 7. But even with that he needed the password to be able to use Material Burst. His Decomposition or Regrowth are not better without the limiter, same for Elemental Sight, his weak normal magic can't be strengthened too, Gram spells work via concentration of huge quantity Psions so I don't see how the power can be strengthened when he is able to spam it but it would be the only improvement at best.
So Tatsuya is not that limited when he fights.

[Navinor]

Originally Posted by Echizen777

I am not saying that we know everything about him but to say that we don't know his true powers is exaggerated. We know all his techniques, Miyuki is the limiter who can affect his powers to various levels, he was at full power in Vol 7. But even with that he needed the password to be able to use Material Burst. His Decomposition or Regrowth are not better without the limiter, same for Elemental Sight, his weak normal magic can't be strengthened too, Gram spells work via concentration of huge quantity Psions so I don't see how the power can be strengthened when he is able to spam it but it would be the only improvement at best.
So Tatsuya is not that limited when he fights.

Yes. But that would not be enough to beat Maya.

And as Tatsuya said to Miyuki. At the moment he is not strong enough to fight against Maya and the Yotsuba.

Maybe some of the limiters are hiding powers in his brain, he acatually even himself do not know about.

Because even in Vol. 7 not ALL of the limiters were removed. And because of that he is feared by Maya and the Yotsuba.

He can pull this things off, even with his "weak" magic at the moment.

And do not forget. He is "Taurs Silver". There will always be improvement for CADs.

[Echizen777]

Originally Posted by Navinor

Yes. But that would not be enough to beat Maya.

And as Tatsuya said to Miyuki. At the moment he is not strong enough to fight against Maya and the Yotsuba.

Maybe some of the limiters are hiding powers in his brain, he acatually even himself do not know about.

Because even in Vol. 7 not ALL of the limiters were removed. And because of that he is feared by Maya and the Yotsuba.

He can pull this things off, even with his "weak" magic at the moment.

And do not forget. He is "Taurs Silver". There will always be improvement for CADs.

No he doesn't need to be without limiters to beat Maya, he could have killed here in vol 8. He can kill her because Gram Dispersion counters Meteor Stream.

And he was at full power in vol 7

Spoiler for Proof:

Miyuki wasn't just sealing Tatsuya's power.
In order to seal Tatsuya's power, Miyuki spent half of her own magic
on her brother.
The fact that Miyuki's magic went out of control was a side effect of
suppressing her brother's magic.
Now, with Tatsuya's might unleashed, Miyuki's personal power was
also released.
The Yotsuba Family did not have a signature appellation.

It's like that: Tatsuya at full power has access to Material Burst and more psions, these 2 are not really important in battle because nobody is even close to have a psion count comparable to him excepted his father.
Miyuki can't use Cocytus without the 50% used to reduce Tatsuya's psion count and her control is less good, though it's not a problem as long as she is not fighting a worthy opponent like Lina. Her MP is not literally twice as powerful when Tatsuya is unleashed.

Miyuki can limit his power to various levels and there is the password. These 2 factors plus his emotional problems make him unable to nuke his clan of his own will.

CAD improvement will benefit to everyone but it certainly won't make him able to wield powerful offensive magics other than Mist Dispersion. His innate magics are at their peak, complete Decomposition and almost instant Restoration.

[mrSh4dy]

Originally Posted by amtro

You do realize that he can just fuse sufficient hydrogen atoms to create the other atoms, right?
Regardless, the conversion of energy to mass is a theoretically sound phenomenon.

Huh what?
You mean fusion?
Other then needing several other atoms, it requires a red giant, supergiants and a supernovae before he has formed the periodic table.

Obviously this all way too abstract for any story teller to think off. But he's always giving us these major info dumps telling about this magic world, how it works and whatnot. It's just that regrowth breaks the world he set up and I'm just trying to find a logical conclusion that explains regrowth in-universe.

Originally Posted by Echizen777

His arm will reattach almost instantly once it's cut due to the speed but if he willfully suppresses it another one will be created. It copies his Eidos from the past in the ID and the information is pasted on his physical body. His Restoration in the animation depicted it well IMO. Time is rewinded only in the Information Dimension.

Against Lina it was not cut but was disintegrated, it will be the same. But if he had been in this state for more than 24 hours he would have kept one arm forever.

So basically you're saying he creates something out of nothing?
Or otherwise uses a special particle that can form into the "information" of what used to be, to recreate said "information", but why is only Tatsuya able to manipulate that particle to form something into existence?


The mahouka world has its basis in science and then uses the term magician for those that manipulate the world and it's rules. But what regrowth does is basically breaking the rules and invent some deus ex machina particle, either that or the author just doesn't have the answer.

[Sinarblood]

Originally Posted by mrSh4dy

Huh what?
You mean fusion?
Other then needing several other atoms, it requires a red giant, supergiants and a supernovae before he has formed the periodic table.

Obviously this all way too abstract for any story teller to think off. But he's always giving us these major info dumps telling about this magic world, how it works and whatnot. It's just that regrowth breaks the world he set up and I'm just trying to find a logical conclusion that explains regrowth in-universe.

Regrowth breaks nothing, it uses the exact same material that was damaged in the first place. It only rewinds things back to how they were, it creates no matter. Even if hit by Broniac, it is not like the atoms in the arm have turned into energy, they are still there (vapourized but not energy), and regrowth gathers them all back into an arm. Remember how it was mentioned when he repaired his CAD in the Lina fight it stated he used it coordinate information to have all the parts reform in his hand, it is the same thing, the coordinate information relative to the body is used and they are restored. If Tatsuya's arm was cut off, and he used regrowth, there would be no cut off arm on the ground beside him as it would have been used in regrowth. Regrowth creates no matter, it reads the Eidos and restores to a previous state using matter that already was part of that Eidos at the state it was restored to.

The most one could argue about is whether or not it allows the teleportation of inanimate objects to places they have been before, using coordinate information (I highly doubt it could do so to living being entirely as Tatsuya's magic has no effect on the Pushion information body (hence why he couldn't simply decompose the parasites), so that would be like separating the mind and body). As there has only been shown to be multiple Pseudo-teleportation spells and no true ones, it could be argued whether or not this potential aspect breaks the rules of the Mahouka world, but I think that it doesn't as no true teleportation spells only imply that it has not yet been discovered and if regrowth can affect inanimate objects in that way, it is very restricted only to places the item has been before in the last 24 hours.

[mrSh4dy]

Originally Posted by Sinarblood

Regrowth breaks nothing, it uses the exact same material that was damaged in the first place. It only rewinds things back to how they were, it creates no matter. Even if hit by Broniac, it is not like the atoms in the arm have turned into energy, they are still there (vapourized but not energy), and regrowth gathers them all back into an arm. Remember how it was mentioned when he repaired his CAD in the Lina fight it stated he used it coordinate information to have all the parts reform in his hand, it is the same thing, the coordinate information relative to the body is used and they are restored. If Tatsuya's arm was cut off, and he used regrowth, there would be no cut off arm on the ground beside him as it would have been used in regrowth. Regrowth creates no matter, it reads the Eidos and restores to a previous state using matter that already was part of that Eidos at the state it was restored to.

The most one could argue about is whether or not it allows the teleportation of inanimate objects to places they have been before, using coordinate information (I highly doubt it could do so to living being entirely as Tatsuya's magic has no effect on the Pushion information body (hence why he couldn't simply decompose the parasites), so that would be like separating the mind and body). As there has only been shown to be multiple Pseudo-teleportation spells and no true ones, it could be argued whether or not this potential aspect breaks the rules of the Mahouka world, but I think that it doesn't as no true teleportation spells only imply that it has not yet been discovered and if regrowth can affect inanimate objects in that way, it is very restricted only to places the item has been before in the last 24 hours.

The only problem with that is the speed at which he does it. It's almost instantaneous, but it's a hell of a lot better then magical clay like particles that replace whatever is missing, so let's go with that.

[amtro]

This is unrelated to the current discussion, but it's a common misconception among the fans of mahouka, so I'll correct it here and hope that people read it.
Tatsuya's natural interference strength is not inferior to Miyuki's own, in fact it is greater.

Spoiler for vol 6:

"Hey, flattery won't get anything from me. You are capable of using magic at a wider scale than I can, and if you weren't constantly keeping an eye on me, you would be able to do this too. In terms of defense, you are far ahead of me, aren't you?"

"In that case, can't Onii-sama reach even farther than I can by increasing the level of interference?"

It's his artificial MCA that has inferior interference strength.

[Echizen777]

Originally Posted by amtro

This is unrelated to the current discussion, but it's a common misconception among the fans of mahouka, so I'll correct it here and hope that people read it.
Tatsuya's natural interference strength is not inferior to Miyuki's own, in fact it is greater.

Spoiler for vol 6:

"Hey, flattery won't get anything from me. You are capable of using magic at a wider scale than I can, and if you weren't constantly keeping an eye on me, you would be able to do this too. In terms of defense, you are far ahead of me, aren't you?"

"In that case, can't Onii-sama reach even farther than I can by increasing the level of interference?"

It's his artificial MCA that has inferior interference strength.

That's not the same. He said himself it's because it was his area of predilection, he was decomposing stuff. Tatsuya is not born with IS= strength to rewrite Eidos, otherwise he would not be considered as a fake magician by his clan. Miyuki is just being a total brocon here as noted in the text itself.

So far nobody has more IS than her excepted Katsuto.

[amtro]

Can you find me the passage that confirms that Tatsuya doesn't have IS? I'm sorry, but if you're getting this from just 'inferring' then that's not going to cut it.

[Echizen777]

Originally Posted by amtro

Can you find me the passage that confirms that Tatsuya doesn't have IS? I'm sorry, but if you're getting this from just 'inferring' then that's not going to cut it.

IS is the strength to rewrite Eidos, everybody able to do this is a magician. Tatsuya could not rewrite Eidos before the operation, just break it down and reconstruct it. So he had no IS. There is nothing wrong with this reasoning. If he had IS, he would have been able to use systematic magic.

Spoiler for Vol 8:

"From the time he was born, Tatsuya could use only two types of ‘magic’.
Decomposition of Eidos, and reconstruction of Information Bodies. Within the
concept of these two categories Tatsuya has devised a variety of techniques
he can use, but however far you take them, with just those two, it is
impossible to alter Information Bodies as a true magician should."
Her eyes simply stared into nothingness.
"Magic are the techniques which modify Information bodies, and thus change
phenomena. However trivial the change is, to be able to make the change at
all is magic. But Tatsuya is unable to do that. All he can do is break an
Information Body down, and recreate it back in an earlier state. That is not
magic in its truest sense. That child, who was born without the talent to use
magic in the true sense of the term in altering Information Bodies, is
unquestionably a defective magician."

[Sinarblood]

Originally Posted by Echizen777

IS is the strength to rewrite Eidos, everybody able to do this is a magician. Tatsuya could not rewrite Eidos before the operation, just break it down and reconstruct it. So he had no IS. There is nothing wrong with this reasoning. If he had IS, he would have been able to use systematic magic.

Spoiler for Vol 8:

"From the time he was born, Tatsuya could use only two types of ‘magic’.
Decomposition of Eidos, and reconstruction of Information Bodies. Within the
concept of these two categories Tatsuya has devised a variety of techniques
he can use, but however far you take them, with just those two, it is
impossible to alter Information Bodies as a true magician should."
Her eyes simply stared into nothingness.
"Magic are the techniques which modify Information bodies, and thus change
phenomena. However trivial the change is, to be able to make the change at
all is magic. But Tatsuya is unable to do that. All he can do is break an
Information Body down, and recreate it back in an earlier state. That is not
magic in its truest sense. That child, who was born without the talent to use
magic in the true sense of the term in altering Information Bodies, is
unquestionably a defective magician."

To be a bit more specific interference strength doesn't simply have to do with rewriting the Eidos, it also has to do with casting a spell on an Eidos that is already being affected by magic. If the original spell's IS is higher, a second spell with lower IS cannot affect that Eidos until the first spell is done. This is what lead to the original flaws with making flying type magic. That said, Tatsuya's abilities with normal magic is said to be low, with imply low inteference strength with modern magic (and no interference strength with modern magic at all until the operation, of course). That said, it doesn't say anything about his specializations as IS isn't the same for an individual across the board as implied with Maya:

Spoiler:

Just as it’s impossible to defend against by magic which shields against physical phenomena, it’s almost impossible to defend against Meteor Line with anti magic. Since it’s mediated via the physical phenomenon called light, preventing it purely via anti magic such as interference over an area is extremely difficult. If one’s interference strength in the single element ‘distribution of light’ cannot exceed Maya’s, ‘Meteor Line’ is unstoppable. As ‘distribution of light’ is Maya’s innate magic, interfering with it is far too high a hurdle. And once the magic has been activated, even if one tries to cause interference in the area of effect, the phenomena rewriting effect that ‘light has moved’ has already taken place.

which implies that IS can apply to "single elements". So Tatsuya's Decomp and Regrowth might have a high Interference strength (allowing them to be cast on an Eidos that already has a spell working on it), even if it sucks for all his other magic. The only thing is that he usually uses counter-magic on things, and he has been stated (via trident) to be able to decompose data-fortification, and zone interference, so Interference strength hasn't really come into play much with him, unlike with other magical technicians.

If it did, and someone for instance cast a spell that targeted their entire body decomposition's IS would have to be greater than their spells to work, but in reality since his counter magic is so strong (and not dependent on his IS at all), that spell would either be countered before the spell was cast, or stripped away as soon as it was done, so really it doesn't come into play.

That said, due to Amtro's quote, and the fact that Decomposition and regrowth is his specialized innate magic, like distribution of light is Maya's, when it comes to those skills I'd have to say that he has exceedingly high IS, even if it is terrible for anything else.

Fun fact: when looking through volume 1 when making this post I found a contradiction on whether or not interference strength is tested in rankings and in the high school:

Spoiler for volume1 isn't tested:

"It doesn't matter if it's multi-variable quantitative processing speed, calculation scale, or even interference strength. None of these are subjects that are assigned a grade."

and

Spoiler for volume 1 is tested:

Selection and ranking are based on Magic Sequence design and usage speeds, scale, and interference strength, which were the exact same scales used in high school technical skills testing.

This is probably due to a translation error, but I'd just thought I'd point it out.
I am pretty sure it is tested (the first quote probably being the translation error) but it is a neat little error regardless

Edit: thought I'd include this quote

Spoiler for volume 3:

Unfortunately, Magic Sequences are unable to affect other Magic Sequences. Magic Sequences can only be used to affect the Information Body, even if two types of magic are both trying to influence the same Information Body, only the one with the stronger interference strength would actually manifest, as Magic Sequences don't possess a strong versus weak relationship.

as proof that IS does not only has to do with rewriting the Eidos, but with the interaction of magic sequences in general.

[Echizen777]

^Totally agree with you.

His magic directly interferes with the structural information, it's not the same as the others which alter Eidos, so saying that he has higher IS than Miyuki and the likes is wrong. He has no IS for that kind of thing but a magic which interferes directly with the information structure instead of sending fake signals and stuff. So far there is not a true name to qualify this but it is not Interference Strength, he had no IS and with the operation he gained a low one.

To be able to interfere directly with the information structure(Gram Dispersion) is what makes this counter magic better than Gram Demolition which would have permitted him to decompose all of Masaki's bullets.

[Jirachier]

Tatsuya has Interference Strength, it's just he has two values or it, one for his artificial magic calculation area which is at a really weak level, and another value for his innate magic that is a very powerful interference.

[I'm-here-present]

That only pictures out perfectly the image of a mage-killer on Tatsuya. His skills are all set to negate other magicians' magic.

[Forbin]

Originally Posted by mrSh4dy

That still doesn't explain where he get's the material from.

Eidos are the data of the world and they form the core of that what we see (I got that mixed up earlier).
Now normal mahouka magic is about making changes to the Eidos while the natural balance in the world eventually reverts this back to normal. This is because the data can not be changed externally, but because Tatsuya ability uses the already established data to reform itself it won't be overwritten.
I get that, however what is used to recreate that arm. The human body exists as data in the Information Dimension but in the corporeal world it exists as

Elements in the Human Body
Element Percent by Mass
Oxygen 65
Carbon 18
Hydrogen 10
Nitrogen 3
Calcium 1.5
Phosphorus 1.2
Potassium 0.2
Sulfur 0.2
Chlorine 0.2
Sodium 0.1
Magnesium 0.05
Iron, Cobalt, Copper, Zinc, Iodine
Selenium, Fluorine

Now my problem is where do the elements come from to restore that arm.
-If he cuts of his arm does he regrow it and have 2?
But what did he use to reconstruct his new arm with the 1st one still around?
-If he cuts of his arm does he somewhat partially rewind time which reattaches his arm?
Considering the speed and how it is described this doesn't fit.

This is where I'm lost as to what he actually does.

So you are implying that there can be TWO tatsuya's if we cut him in half?

I think the Dr wanted to try an experiment like that during his discussion with Fujibashi during the 9SC