Illumi's departure did not dampen Serik's spirit. He knew they would meet again, and for now his focus was on recovery so he could continue training his Hatsu. At present, the only limitation he had imposed on himself was the requirement to use a hand seal to manipulate the earth. While it did not provide a significant boost, it was sufficient.
What concerned him most, however, was the path forward. Ever since waking up, he had been thinking about the direction he wanted to take with his ability. As a Specialist, it needed to incorporate at least four Nen categories. He needed guidance. Fortunately, he had both a highly capable butler and an even more capable grandfather—someone who had undoubtedly faced a similar dilemma in the past.
An hour after Illumi left, Jons entered the room carrying a tray of food. Serik slowly sat upright as Jons placed it on his lap.
"Delicious as always," Serik said.
"You are too kind, young master," Jons replied.
While eating, Serik asked, "Jons, how should I further develop my ability?"
Jons did not answer immediately. Instead, he gave a small smile and left the room. A minute later, he returned carrying a book. Serik recognized it instantly—it was unmistakably his childhood storybook.
What happened next nearly shattered his worldview.
Jons began infusing Nen into the book. In response, unfamiliar symbols appeared across its surface. The symbols moved across the cover and toward the pages as the book shimmered with a soft golden light. Within seconds, the symbols vanished entirely. Only then did Jons hand the book to Serik.
"Young master," Jons said, "this was never just a book of fairy tales. Inside are the results of your grandfather's research into Nen—nearly everything he worked on until the end."
Serik sat frozen, mouth agape. After a moment, once the weight of the revelation settled in, he asked in confusion, "Why didn't you give this to me earlier, when I started training?"
"What is written in this book is not meant for beginners," Jons replied calmly. "It is far too complex. Even now, much of it is beyond your current understanding. The only section relevant to you at this stage is the chapter on ability creation and development."
Hearing this, Serik immediately set his food aside and began reading. Seeing this, Jons quietly took the tray and left the room without a word.
Ability creation is not inherently difficult. The true problem lies not within the Nen system itself, but in how poorly it is understood and disseminated. Because Nen has never been widely taught nor systematically developed, most users approach ability design through instinct, imitation, or superstition. As a result, abilities tend to be either overly simplistic and quickly outgrown, or so complex that they collapse under the weight of their own restrictions. Strange vows and excessive limitations are not born from necessity, but from a lack of direction.
In reality, there exist several established paths of ability creation, largely independent of Nen category. The most commonly recognized is the growth-type path. In this approach, an ability develops alongside its user. The core remains stable, while new functions, refinements, or efficiencies are unlocked as the user gains experience, insight, or control. Growth-type abilities require patience, but in the long term they are among the most stable and powerful, particularly for individuals with a clearly defined personal path.
Another well-documented path is the modular-type. Here, an ability is constructed around a fixed core with expandable components. New functions are added as separate modules rather than by altering the core itself, preventing structural instability. The strength of a modular ability lies not in raw output, but in adaptability. Users following this path build systems rather than isolated techniques.
Closely related, yet often misunderstood, is the conditional-type path. In this model, the ability itself remains constant, but its effects change depending on context, environment, or target. This is frequently confused with restrictive vows, but the distinction is critical. Conditions are not self-imposed penalties; they are logical switches built into the ability's design. The ability responds differently to circumstances without requiring the user to sacrifice power or freedom.
Some Nen users design their abilities around function rather than form, a method known as the role-based type. These abilities are optimized for specific purposes such as control, support, reconnaissance, containment, or execution. Within their intended role, such abilities perform exceptionally well, but they are not meant to dominate every situation. This path is often undervalued due to the common misconception that all Nen abilities must be suited for direct combat.
A more complex but highly efficient approach is the resource-type path. Rather than relying solely on aura output, these abilities operate through the management of alternative resources such as time, information, preparation, stored Nen, positioning, or environmental factors. Their effectiveness scales with the user's ability to manage these resources intelligently. Impulsive behavior is punished, while foresight and discipline are rewarded.
The rule-based type represents a further refinement. Abilities following this path function as internal systems governed by fixed laws. Once predefined conditions are met, the effect activates automatically, without the need for continuous user input. These are not vows, but intrinsic rules of the ability itself. When properly designed, rule-based abilities are mentally efficient, consistent, and extremely reliable.
There also exists the expression-type, in which an ability is a direct manifestation of the user's identity, beliefs, or psychological structure. Such abilities feel natural to their users and require minimal mental strain to maintain. Because Nen responds strongly to self-image and conviction, abilities that align closely with their creator tend to be more stable and effective, even without heavy restrictions.
Finally, the interaction-type path focuses on response rather than initiation. These abilities activate, scale, or evolve based on the actions or behavior of others. Observation, patience, and timing are prioritized over speed or aggression. Instead of forcing an outcome, the user allows opponents to unknowingly trigger or strengthen the ability themselves.
Truly powerful Nen abilities rarely follow only one of these paths. Most combine two or three in a coherent and deliberate structure. When an ability is logically designed, mentally sustainable, and aligned with its user, extreme vows become unnecessary. In Nen, power is not born from self-destruction, but from understanding.
Serik held his head as a dull throb spread behind his eyes.Too much information.
He exhaled slowly and began flipping through the pages, skimming past sections he barely understood, until his eyes caught on a familiar heading.
Specialist
A Specialist ability must, by necessity, incorporate multiple Nen categories. At minimum, three are required for structural stability. This is not a rule imposed by Nen, but a conclusion drawn from repeated observation.
A Specialist who relies on a single category produces an incomplete system. Such abilities are either fragile, overly conditional, or prone to collapse under strain.
Furthermore, a Specialist's first ability should never be bound by heavy vows or extreme limitations. An undeveloped system cannot bear excessive constraints. The foundation must be built on comprehension, adaptability, and growth before sacrifice is introduced.
Serik frowned.
"What in the name of Nen does he mean by that…?"
The explanation continued.
If this is difficult to understand, think of it this way: a Specialist must build an ecosystem.
A forest is not made of trees alone. It consists of soil, plants, insects, animals, and microorganisms. Each element is inseparable from the others, and none can thrive in isolation. Growth in one part of the system influences the whole—when the soil becomes richer, the trees grow stronger; when the trees grow, they shelter the life beneath them.
A Specialist ability must function in the same manner. It cannot rely on a single Nen category or a single mechanism. Each component must support the others, allowing the ability to grow naturally as its variables develop. When one aspect improves, the entire system becomes stronger.
Serik leaned back slightly.
"An ecosystem, huh…"