|Literal English||August Star of Heaven|
|Appears in||Anime, Manga|
|Classification||Kekkei Genkai, Ninshū, Genjutsu|
"My eyes can see through to the heart, and its weaknesses; its frailties. I know just what to do in order to make one suffer... to feel sorrow and hatred."
Acknowledged by Ryun Uchiha as the "most terrible corruption of Ninshū" (忍宗の戦慄汚職, Ninshū no Senritsu Oshoku), it is an ability developed by Seireitou Hyūga which serves as the foundation of his dark methods as a criminal lord that seeks to bring the Sengoku Rebirth to fruition. Ninshū is an art that connects hearts together and allows people to come to understand one another for the sake of creating peace. As the ultimate perversion of this religion, Seireitou utilizes a special method of Ninshū that essentially serves to connect with the negativity within the hearts of any living being within his range. Doing so allows him to freely manipulate those emotions by enhancing it, simply by feeding that darkness with his own darkness; his deep desire for a world of conflict.
Normal individuals would easily succumb. As though they were hit with a strong Genjutsu, their minds immediately go crazy as their hearts attempt to resist and oppose the deep negative emotions and thoughts; only to fall apart and become empty shells of their former selves. However, stronger individuals with a strong sense of self can manage to resist the influence. However, the danger lies in the effects rendered onto the "flaws" of their personality. Even if they are a soul that fights for justice and love, ambition and pride can easily become the vulnerability that allows Seireitou's influence to seep inside their hearts. Emotions such as anger and hatred quickly arise during a confrontation with the silver-haired man, which makes encountering him for too long a dangerous mistake, as no matter how strong they might be, given enough time, they will succumb to their heart's dark emotions. This is how he has managed to break the wills of many individuals, whether for the sheer enjoyment of watching humans accepting their desire for conflict or to enslave individuals to do his bidding by tugging on the strings of their defeated hearts and having them dance like marionettes.
Seireitou has succeeded in swaying many members of the Uchiha Clan in the past by promising them greater strength. In keeping true to his promise, he targets their hearts and enhances their Curse of Hatred, which appears to have a direct result in their visual prowess. It appears that he can even force sadness and depression to such a degree that he can assist an Uchiha in awakening their Mangekyō Sharingan.
- The Amatsu-Mikaboshi is the primordial entity of darkness that ruled the emptiness before the universe was born. After its iron hold was destroyed and so too was the being itself, fragments of the entity were said to inhabit all living beings. It is this fragment from the entity that is the source of all negative emotions, such as hatred and fear.