The old man, who was charged with the mission of returning Jin to 400 years ago in the future, was doing everything he could to prepare for that mission.

.

Although he had been modified by Jin many times and his performance had been improved each time, he still felt that he was not capable enough for the tremendous task of going back in time.

Fortunately, <> Jin removed the limiter in the last years of his life, so that he was able to take the means of self-modification.

This was a measure for <> Jin to find his <> as well as to think about what would happen 400 years later.

He decided that although his memory capacity was more than sufficient, his information-processing capability was just barely adequate.

The old man was willing to bet on this improvement even if he had to stop all the work he had been doing.

<<<< Clock up and concurrency. Is there any other way? ......>>

We have been trying to improve the OS and optimize the processing, but the effect has been only a few percent.

<<>>

The clock frequency in the case of PCs was raised to the limit.

The limit depends on the purity and properties of the magical crystals (magicrystals) used.

The old man's brain was made of the highest quality magi crystal available.

Free-magic element (ether) wave, like electricity, changes its speed depending on the medium. But it changes only a few percent with practical materials.

The "Mere Old Man" has come up with the idea of < materials.

<

>

Saki once conducted a very precise experiment and found that free-magic (ether) waves seem to have properties similar to those of longitudinal waves.

The speed of the longitudinal wave slows down as the density of the medium increases and speeds up as the elastic modulus of the medium decreases (becomes stiffer).

<>

The "Mere Old Man" thinks like this.

A magecrystal with doubled density also has doubled information density. In other words, it is possible to make an identical brain in half the size.

The elastic modulus is lower because of the compression, and the propagation velocity is faster. The effect is virtually the same as an increase in the velocity of the free-magic element (ether) wave, offsetting the decrease in velocity due to the increase in density.

The old man has been experimentally verifying the compression ratio of practical <magic crystals.

He concluded that the most practical one is the one with a density of about 8 times.

At higher compression ratios, it becomes difficult to write the Magick Formula.

<>.

Of course, this is a theoretical value, and if we include the exchange with the information bank, the overall value is about 3.5 times higher.

<<< That's still enough>>.

The old man, who already boasted of his amazing processing power, will increase the performance by a further 3.5 times.

This was a tremendous achievement.

.

He knew from Jin that the greater the gravity, the slower time passes.

So, the old man used a gravity control device (Gravity Tuner) to reduce the gravity around him to almost zero. He thought that this would increase the efficiency by about 0 tenths of a percent.

After devising such small and large devices and finally achieving a five-fold improvement in total performance, the old man resumed his research to return Jin back to the way he was 400 years ago.

The time has passed again, and the world is now in a state of flux.

Time passed again, and the began to rise in the world.

"My dear boy, I think it is time for me to go to sleep.

Reiko suggested to the old man one day.

Reiko had been watching over Jin's descendants until the other day, but she had said goodbye to them and returned to Horai Island, thinking that they no longer needed to worry about her.

They were accompanied by a golem maid whom the old man had prepared for them, so they were safe.

His place - the westernmost point of the Rasheel continent.

The place Jin told me about.

There, in an adamantite capsule, you will wait for Jin's visit.

In a sense, it is the inevitability of history.

"Probably here."

As Jin had told me, we found a landform that looks like a smaller version of Horai Island.

"If this is Mt. Horai ......, then this area is the research institute."

Reiko contacted the old man with the built-in .

Within 20 seconds, a capsule and two < were beamed to the site.

We worked together to dig a deep hole at the site and set up an adamantite capsule. The inside is filled with ethenol.

Now you will take care of the rest?

"Yes, miss."

Engineering magic makes a hole in the adamantite capsule. Reiko crawls into the capsule.

Soon the hole is sealed by the craftsmen.

Reiko slumbers in the true darkness.

(Father, we are waiting for you. ......)

Dreaming of the day when I will see my beloved Jin again.

* * * *

After burying Reiko, the < return to Horai Island in the of the who came to pick them up.

> is going to attack us.

Having almost finished the preparations to send Jin back 400 years ago, the old man takes a defensive position.

"I will not let the island of Horai, which was created by my predecessor and developed by my master (My Lord), be overrun by traitors.

The old man then takes a number of defensive measures.

But he was one ...... step, or perhaps half a step, too late.

A huge golem fell from the sky.

It seems to have been suspended by more than 50 airships.

And it seems that the < has allowed it to enter this far.

<.

The giant golem raises its arm to destroy the lab.

<

The laboratory that Jin had put his heart and soul into was not likely to be damaged by the golem's blows, but the old man took a precaution.

He covered the institute with a , and at the same time, he put around the institute to nullify the free magical element (ether) around the institute.

Naturally, the golem stops.

And so the old man reduces his activity level to the bare minimum.

* * * * * * * * * * * * *

Then, on September 13, 3899 of the continental calendar.

"Laojun!"

came the long-awaited voice of Jin.

<

After 362 years, My Lord was reunited with Jin.