All of this is an illusion created by this terrifying Fuinjutsu.
However, behind all the suffering felt in the illusionary world, there is something deeper—something that Reiji designed very carefully: Target Separation Based on Condition.
Anyone who experiences "death" in that world will fall in the real world, their bodies collapsing helplessly, as if they have truly died.
However, those who choose to give up in the fight—who end everything with a conscious choice—will remain standing, even though their minds are still trapped in that world full of illusions.
When this Fuinjutsu is finally stopped, the world built in the mind begins to collapse, as if sunlight disperses thick fog.
Yet, even though that world disappears, traces of it remain.
People who chose to surrender will awaken in a standing position, their breath returning, and their bodies feeling stiff—still trapped in the memories of experiences they never truly had.
Meanwhile, those who were "killed" will awaken lying down, their bodies feeling as if they bear the weight of the death they just experienced—one burden they carry in every movement.
The Illusion Sea Domain is not just a training space.
It is a new world, an alternative world that can be shaped and destroyed with a single decision.
Within it, ninjas can face their fears, delve into the depths of their emotions, and hone their skills without the risk of losing their lives.
Reiji created this not just as a tool for training, but as a means to force them to confront the deepest parts of themselves.
Every fight in the illusionary world is a mirror of the strength that exists within them, and every defeat is a valuable lesson.
In this way, the members of the Uzumaki Clan can experience the most real battles—the biting pain, wounds that seem to gnaw at their bodies, and death that comes without warning.
Yet, in every battle, they learn to endure—to rise, to fight, and to become stronger.
And, more than that, there is a greater purpose hidden behind it all.
The Illusion Sea Domain is the first step towards something much greater.
Reiji understands that by creating this technique, he has opened the gateway to the development of more complex and profound Fuinjutsu.
An initial foundation that will shape the future not only for the Uzumaki Clan but also for the ninja world as a whole.
The Illusion Sea Domain becomes an important stepping stone to give birth to a generation of ninjas that are stronger, wiser, and more prepared to face the harsh realities of the world—far harsher than any illusion that can be created.
This technique not only serves as a defensive tool but also as a revolutionary training platform: a realistic illusionary world where the Uzumaki Clan ninjas can practice and fight against each other without fear of injury or loss of life.
This virtual world is built from high-level illusion Fuinjutsu, creating combat experiences as accurate as possible, without permanent risk.
The use of illusion-based Fuinjutsu is also a natural advantage for Reiji.
In his previous life, Reiji had mastered the art of illusion deeply, and now he combines it with Fuinjutsu to create efficient techniques.
On the other hand, building the Island Protection Fuinjutsu requires much longer time and preparation.
Therefore, Reiji chose to complete the Illusion Sea Domain first—faster, more strategic, and still providing initial protection for the Whirlpool Island.
After completing this technique, Reiji could shift his focus: continuing the development of the island defense Fuinjutsu, creating new techniques, or preparing other steps to strengthen the Uzumaki Clan.
This decision proved to be the right one.
When a combined attack from three major villages came—with more than three thousand ninjas storming the Whirlpool Island—Reiji faced them not with frontal violence, but with intelligence and silent traps.
------------------------------
[Announcement: A New Novel Has Been Added!
The Puppet Maker in the World of Naruto
A man who is a scientist, researcher, and expert mechanic in robotics dies in a massive explosion that occurs in his laboratory while developing an advanced robot project. However, instead of experiencing death as he thought, the man awakens in another world—a strange place with vast stretches of desert.
There, the man is surrounded by people who can jump high, calling themselves ninjas. The confusion he initially felt grows as he realizes that this world is not unfamiliar to him. This is the world of Naruto! However, there is one thing that surprises him.
"Isn't this Sunagakure? Why am I not in Konoha? This poorest village... Oh my God, this is serious!"
Now, in the midst of a new life filled with danger and uncertainty, the scientist must find a way to survive in Sunagakure, a harsh place full of limitations. With his robotic knowledge, can the man change his fate in this ninja world, or will he fall along with the village?]
________________________
[Note: 580+ latest chapters have been added! For Just 3$ You Get Access To Chapters Way Ahead,
Now you can access the chapters before Webnovel And Scribblehub by following,
Just become a patron on Patreon:
Patreon.com/Alex_Fabianoki]