Conscious strengthening of Nen

Nen responds to the goals and strengths of the desire of its user. As a result, a user can make a commitment that results in an increase in their abilities. If a user, for example, damages their own body in such a way that an individual skill seems more imposing when used, their Nen will become correspondingly more powerful. It is also possible to increase the strength of an individual skill by imposing limits on it. For example, if a user consciously decides something along the lines of "I will only use this skill on Thursdays," or "I will only use this skill against short people," and manage to abide by the rule, that particular skill will become stronger.

Theoretically, the more restrictive the condition, the greater the enhancement in power. It is also implied that restrictions which carry great meaning, or emotional value also bring about a greater benefit.

Furthermore, restrictions which contain some sort of 'punishment' (i.e. "I will die should I break this rule") will strengthen the ability more.

One example of this is the character Kurapika, who swore by death not to use one ability of his, called "chain jail", on anyone but a group known as the Phantom Troupe, more commonly known as the "spiders".