Published: July 3, 2025
On this day (June 14), I decided to make an additional post on Sunday... for some reason...
The next chapter '0101' will be posted today at 9 PM as usual.
After leaving the City of Kairadi, there were no problems until the morning of the second day.
While they were on their lunch break, Ryo spoke to Ra.
"It seems like two people have been keeping their distance and watching this merchant convoy."
"What!?"
Upon hearing Ryo's report, Ra took him to the captain of the guard, Max.
"Max, it seems there are two people monitoring this convoy. Ryo said so."
"They could be thief scouts. Ryo, without moving your gaze, tell me where they are."
"About four hundred meters ahead in the trees, and one on the ground at a similar distance behind. One each."
Ryo faced Max while conveying the information he had gathered.
"Four hundred meters... how did you spot them from that far away?"
"There's a perfect spell for just this situation in water attribute magic."
Max was surprised that Ryo noticed the sentries from such a distance.
In Ryo's case, using active sonar, he could perceive things almost a kilometer away.
However, if the target is sensitive, they can notice the active sonar.
At the very least, the target would know that someone is probing.
In fact, when they were trapped in the sealed corridor, when Ryo first used active sonar, Demon Leonor retaliated from a distance where he couldn't be seen.
That's how it works.
However, as in this case, Ryo refers to it as passive sonar, and if it is a passive sonar, the target will not notice it.
Now, in the world, there are terms like 'presence' or 'sensing presence.'
Of course, scientifically defined concepts do not exist even in the 21st century on Earth.
However, almost no one would doubt its existence.
It could be the scent emitted by the target, the change in airflow caused by the target's presence, or the change in how sounds propagate due to the target being present...
Ryo thought these were logically explainable phenomena, albeit elements that are too minuscule to experiment with.
In any case, the one sensing the presence does not take action to feel it.
It is the 'target' that moves, or the change that arises from their presence, which is being sensed... surely.
For example, let's say I am sitting still in water.
What happens if a stone is thrown into that perfectly flat surface of water?
If I wait, the ripples created by the thrown stone will come to me.
By capturing that, I can grasp the size of the object thrown and the distance to me based on how the waves break.
The object that was thrown does not know whether it has been detected by my presence.
And Ryo's passive sonar is an extension of this concept.
He analyzes the information that comes through the air-dispersed water molecules.
Changes caused by the emergence of something that wasn't there before, changes that occur because someone appeared who wasn't there, or changes caused by someone who was there moving.
Captain of the guard Max decided to have the scouts of the guard observe the targets.
He conveyed this to Ryo and Ra, asking them to continue their usual actions.
For the time being, having fulfilled their roles, the two returned to their companions to have lunch.
"I'm glad I could be of some help."
"Yeah, it's incredible that you can spot scouts from that far away with water attribute magic."
Ryo felt relieved to be somewhat appreciated, and Ra honestly praised Ryo's scouting ability.
"I heard before that there aren't any other water attribute magicians in the adventurers' guild besides me, right?"
"Ah... come to think of it, that's true. Water attribute magicians are in demand for jobs in the city rather than dangerous work like adventuring. There should also be several people who can use water attribute magic among Gecko's subordinates, not the guard squad, in this convoy."
"I see! If you're in a merchant convoy, you don't have to carry the water, right?"
"Exactly."
When Ryo looked around, he indeed saw Gecko's subordinates seemingly replenishing water using water attribute magic.