Limitless.
It is the innate cursed technique that is used by Satoru-san throughout the iterations I met him. It works just as its name suggests.
Simply put, it creates an infinite distance between him and the targeted object. It is something similar to imaginary numbers that extend infinitely. He could stand still and let dozens of nuclear bombs hit him, but he'll always come out unscathed. It even works against magic and magical energy in particular.
Logic reasons that such a broken ability should have a limitation—it does. Limitless exerts fatigue to the user's brain. It is the reason why the Gojo Clan doesn't have a huge number of powerful people.
However, Satoru-san is the only exception. With his other gift, [Six Eyes], he could precisely control his cursed energy in such a way that he wouldn't run out of it. It also enabled him to continuously heal his brain through Reversed Cursed Technique.
When the two are combined, it enables him to create a barrier made of infinity for as long as he wants.
I tried to mimic it through magicka and succeeded. All I have to do is to base it around Newton's Third Law. The repulsive force that acts as the 'barrier' should always surpass the attacking force. If the latter is higher, the barrier would be broken.
The price to use it is steep, though. My recovery could barely match it, yes, but I wouldn't be able to use it without my full-blown [Mana Furnace].
Psssh-!
Bam-!
Aiz's rapier was repulsed just as it was about to hit my shoulder. This time, I held her blade with my right hand. The repulsive force acted differently and dispersed the repulsive force within the sword.
Crack-!
Shatter-!
The blade was turned into metal shards as it broke down.
Aiz reacted swiftly and tried to create some distance. I didn't let her do just that. I grasped her right arm before locking it behind her.
She was about to escape when I touched her back. She knew it was a harmless spell that was on my fingertips.
"...It's your win."
"This concludes it, then?"
I released my hold over her arm.
"You really… What's your level?" She asked.
The other two, Tiona and Lefiya, became curious as she asked about it. I singled them out earlier and were eliminated in this spar. Aiz was the last one to be defeated.
"Level five." I said truthfully. "The experiment I did worked wonders."
"..."
Everyone was caught off guard by my words.
I suppose it is that surprising to hear in someone else's perspective.
"Sirius is really something else..!"
"Level five… It would take a few years…"
Tiona was still the same while Aiz and Lefiya got affected by it.
Knowing their personalities, I knew I had to say something.
"I'll be giving a surprise gift later."
"A surprise gift? But isn't it no longer a surprise since you already said it?"
"..."
I admit, that was my mistake.
*****
"Finn-san is still busy?"
"He's currently settling the expedition findings with the guild. It's a matter of cross verification after the demi-spirits showed up."
After the sparring, I headed to the library where I met up with Lady Riveria.
"This is still on me."
"Don't worry about it. He could handle it himself. Don't forget about the deal you gave us half a year ago."
She is pertaining to the huge discount I gave them. Those ninety million valis is a sort of investment for Loki Familia to grow stronger.
In the iteration I saw, Freya Familia is just as strong, but they are not as proactive as Loki Familia. A proof of it was their inactiveness when the demi-spirits struck. Only when it became bad enough did they intervene in the eighth iteration.
It is for such a reason that I built a partnership with Loki Familia.
Soon, our casual talks headed in a certain direction.
"If it is fine with you, I want to ask about the experiment you did."
"Sure."
"How dangerous was it?"
She started off with the main point.
"It depends. I was planning on playing it safe, but things did not go with my plans. It did give me several improvements."
"I see. I thought it was strange for you to take such huge risks."
"I would never do that… unless I was cornered."
Just like my fight with Antares.
Everything occurred around four years in the future. Artemis and her familia ventured around Gekai to help others. When they found a ruined tomb of Antares, one of the strongest monsters before the Black Dragon came, they were surprised by its new form as a cursed spirit.
"About that weird feeling you emit…"
"Oh? Lady Riveria felt it?"
She must be referring to the dormant dream organs I currently have. It has enough strength to obliterate Orario once fully unleashed.
"That was partly the result of my experiment. It served to increase the magicka I could cast. Something similar to a skill of sorts."
"I see." She replied while immersing herself in thoughts. "Your magic… They really are unique."
Hearing her words, I suddenly got curious.
"What's your first impression about it?"
"Impression… It's otherworldly. It felt more advanced than the current magic we have. It's an amazing creation. Whoever taught you is a genius that could only be seen within a millenia."
I smiled at her words. I didn't say anything as I looked at Lady Riveria. It lasted for several seconds before she realized something.
"...Hold on."
I knew it. She was just as sharp in this iteration.
"Am I right..?" She asked. "Did it come from another world..?"
"Partially. It's not just my magicka… but me too. I came from another world."
"..!"
I didn't say anything else.
A few seconds later, she exhaled deeply.
"So that's how it was… It explains everything."
"I apologize if I kept it from everyone." I said. "I have some things I must protect."
"...But why did you choose to tell me it now? Do you want me to keep it a secret?"
"No… Well, it wouldn't matter if you told it to Aiz-san and the others. Even Loki-sama is fine."
Loki Familia is a trustworthy comrade. That was all I could tell when they led others at the forefront and sacrificed many bodies to the fight against the Black Dragon.
Lady Riveria looked at me for a few seconds before nodding.
"While I'm glad you trusted us, you shouldn't tell this to others… Perhaps even Loki-sama might cause trouble in your world. That's how gods are."
Lady Riveria is still her usual self. I didn't expect for her to speak against Loki-sama in this regard.
"Our world is not to be trifled with. We fought and banished gods on quite a regular basis. There are also threats stronger than the Black Dragon. If they did cause trouble, they would be the ones inviting them to Tenkai."
Just the Rank A magicians alone could deal with gods' projections. Magisters like Lord Nettesheim exist, too. Even until now, I haven't fully understood him. He seems to know many things and is one step ahead of everyone.
If Tenkai did try to cause trouble in our world…
Aside from the Twilight Syndrome, those gods from the spirit realm wouldn't sit still. Lastly, I am aware that one other goddess knew about my identity—Freya of Freya Familia. Her eyes are similar to the Magic Pupils that grant a sort of ability.
"I am actually leaving."
"When..?"
"I'll see to it… but it'll be two months at latest."
I couldn't stay here for much longer. After settling the arrangements for Orario and diving on the dungeon's lower floors, I will return to my world. I already have the complete coordinates for the [World Transfer] magicka due to my meeting with Miku.
As for Antares, it wouldn't move from its position. It is something that is verified by the data from the ninth iteration.
I talked with Artemis and convinced her to stay until I returned. By that time, I will bring over some reinforcements before confronting Antares and the Black Dragon.
I will also anchor this world's timeflow to mine to make sure there won't be any potential hiccups. If something does happen to me, there would be backups to guarantee that Gekai won't suffer from its demise.
We talked about some arrangements such as teaching my world's magic systems to them. I also mentioned the Magisters who symbolizes the peak of my world.
"How about this… I can bring everyone to visit my world after my return."
"Visit your world?" She muttered. "It will be interesting…"
"There would also be cakes, parfaits, and several other desserts that don't exist in Orario."
"..."
Lady Riveria hid her fluster with her usual stoicness and silence. I knew about her sweet tooth when I brought over shortcakes once. She prefers her tea to have a matching cake.
"...I admit it caught my attention."
"That's one more thing to look forward to, no?"
Everyone reacts to the things in my world…
That sounds interesting enough.
*****
***
*
Three months later.
"Phew…"
Nobu breathed out as he relaxed his body.
"Eighty-fifth floor… I need to make some improvements."
Ever since he delved into the lower floors, he always has several [Space Anchors] in his possession. These are the rectangular blocks that enabled him to teleport to a 'save point', much like a checkpoint in many games with dungeons.
After stretching for a while, he counted his spoils inside his five-layered storage space.
"The nanomachines ran out… The mobile army couldn't keep up with their spawn rates…"
From the moment nanomachines were successfully invented through his [Miracle Maker], it replaced the conventional blitz strategy Nobu used to employ. Instead of hiding a legion of artilleries and a closed intranet inside several storage spaces, he started deploying nanomachines instead.
It worked for both close and long ranged attacks. All they had to do was to memorize the structures of the said artillery. He only had to bring in ammunition which saved up more space. Of course, those nanomachines have varying metal types.
Nobu refilled his previously-exhausted stock of nanomachines. He directed it to the silver ring on his finger. The seemingly small ring could hold nanomachines that lasted him for three days of continuous battle on the deep floors.
Just as he was about to exit the blank room (multipurpose basement), a familiar itch ran on his chest.
"This is…"
He realized they are about to meet again.
"Galahad."
Out of nowhere, the knight's image manifested in front of him. He wore the same attire as from the ninth iteration.
Instantly, a feeling of solemnity engulfed the room. Galahad, a Heroic Spirit on the level of a Saint, could change his surroundings just by existing.
"This is bad."
His greetings caught Nobu off guard.
"Listen. You are about to be sent into another world."
"Huh?"
Galahad didn't waste much time.
"In our world, Camelot fell due to Mordred's treason. It is the Proper Human History." He said. "However, there's a parallel world that sought us. It is an anomaly among anomalies, a forsaken world about to be destroyed by foreign gods."
Nobu became serious as it went by.
"You can set up the return coordinates after you arrive. You can choose to return to Earth. But… I want to ask a favor."
At this moment, the expressionless Galahad showed a complex look.
"Our king… She went astray. It is painful to see her like that."
As he spoke, a mix of anger and self-reproach could be heard from him. It's as if he is berating himself from not being able to do anything. At the same time, he felt disappointed and angry about his king's approach in that forsaken world.
"After a day passes and you didn't choose to return, it'd be hard to do so again. You'll have to retrieve the Holy Grail Replica or wait until you have sufficient chances to return."
Galahad explained.
"It is up to you to make a choice. I won't force it upon you."
"..."
Nobu closed his eyes and immersed himself into thinking. His current processing speed went off the charts as he reached the status of a level seven within these three months.
'Our king… Artoria Pendragon.'
The once and future king of England.
She was able to raise Camelot's status from Rome's former vassal state into a legendary status.
When he started to slowly retrieve his memories of that dream, Nobu also felt complex to her. In a sense, Galahad's failure to secure the grail contributed to Camelot's downfall. He isn't the type to leave her behind knowing he could do something to make up for his failure.
'Galahad wouldn't show something like this unless it is extremely serious… but I can't have everyone worrying about me.'
Unbeknownst to him, Galahad already changed. If it was the former him, he would remain indifferent to his king's current state. He would reject her summoning without saying anything else.
However, Nobu's human nature altered him slightly. These changes happened as the grail fulfilled his sole wish.
'Alright.'
Nobu connected to the internet in the basement.
[Goshujin-sama?]
A synthetic voice rang on his head.
'Save these records in your database. I might have to disappear for a while.'
[Where are you headed?]
'Another world's Camelot.'
[Understood.]
After pasting the memories on her database, he swiftly opened the hidden storage crates beneath this basement.
He started stuffing his storage devices full with rations and important resources. He also picked up nine other silver rings stored on a shelf and wore it on all his fingers.
'It might be too excessive but it's better to be safe than never.'
"Explicandam." (Deploy.)
Immediately, black nanomachines surged out from one of his rings and enveloped him fully. It only took a moment for them to have a similar shape as his Arbiter. The palladium orinite from it was transformed into a set of nanites.
Of course, all of them are blessed with mysteries to conduct his magicka better.
"Would you really—"
"You said it once. We are the same. Seeing you far detached from what I know explains something."
There are only a few times Galahad broke his stoicness. During those times, he felt extreme emotions.
What Nobu felt while seeing the horrendous state of Camelot after his death is how Galahad would feel if he was the one who saw it.
"Also… I'll be sending Miku back to send a message. I wouldn't leave Gekai alone."
Fuzz-!
A golden-white magic circle appeared on the white ground. A black slit appeared, revealing a sea of stars beyond it.
[Current coordinates lock.]
[Initiating return…]
"I apologize in advance, Miku. It's up to you to tell everyone. Let the plan go as usual."
"{Apology accepted. I will do everything in my full capabilities, goshujin-sama.}"
A combat suit was formed out of nanites. A white line appeared from beyond the black slit which led to a faraway world. Since Nobu was the only one who could cast it in an extremely stable manner, he already chose to do it.
Once the combat suit flew, the black slit closed by itself, and so did the magic circle on the ground.
"I'm ready. You don't have to hold it back."
Hearing this, Galahad simply nodded.
"If that's so… Save our king."
Without any warning, Nobu disappeared from Gekai.
*****
"This is… really…"
Romani was speechless. Just as the fifth singularity was resolved, the sixth singularity's rating changed to EX. For reasons unknown, the readings became extremely blurry. All they could see was that Jerusalem is undergoing unknown changes as of now.
But, it didn't stop there.
The thing that Romani saw previously came true.
A saint was summoned inside the singularity.
A literal Saint.
Oftentimes, they are deployed as Rulers inside the Grail War. However, the Saint summoned this time is comparable to King Solomon himself.
In short, a Heroic Spirit on-par with a Grand Candidate at the very least.
It became clear to Romani that the sixth singularity would be far more difficult than the previous singularity they overcame.
"I hope they could be talked with…"
*****
A/N: This marks the end of the Danmachi arc. It is the first world that this fic went to, hence it is special and had that insane length of 84 chapters. After that is a new world, Fate Grand Order's Sixth Singularity (Divine Realm of the Round Table). I planned for him to return to his original world after that arc. By then, he would be able to steamroll enemies like Jogo and match difficult enemies like Sukuna, Kenjaku, and (of course) the Red Dragon that screwed him over and over.
This is foreshadowed several chapters back. I hope it did not come off as 'out of nowhere'.
PS: Since it is my birthday, I'll be informing everyone that Nobu returns to his world at Chapter 114; exactly fifteen chapters from here. Buckle your seatbelts and enjoy the upcoming 'small' arc. I don't know why but I wasn't able to make these world transitions divisible by 5 (*shrugs*). Anyways, happy reading~!