Tsuchigumo.

Tsuchigumo has two intertwined bodies in Japanese tradition. In the oldest layer, the word is not yet a spider monster at all, but a hostile name used by the Yamato court for local powers described as cave-dwelling, long-limbed, tailed, or otherwise beyond proper civilization. In the later monster tradition, that hostility condenses into a giant spider yōkai, often colossal, web-casting, cave-haunting, and capable of disguising itself as a monk, woman, or servant before striking.

Because of this history, the spider form carries unusual weight. It is not simply an animal magnified into a demon. It is a political insult that becomes flesh, then silk, then nightmare. Medieval picture scrolls and warrior tales make the creature increasingly grotesque, filling its lairs with skulls, lesser spiders, and deceptive apparitions. The result is one of the clearest cases in Japanese folklore where language of human othering turns into a fully supernatural body.

In its historical layer, tsuchigumo marks the encounter between expanding authority and those who resisted it. Court chronicles place tsuchigumo figures in mountains, caves, and frontier zones, and describe imperial conquest in terms that deliberately dehumanize the defeated. In that sense, the earliest tsuchigumo interacts with power as enemy, obstacle, and target of narrative domination.

In medieval legend, those interactions shift to the heroic monster tale. Minamoto no Yorimitsu, already famous for fighting oni, confronts tsuchigumo while ill, vulnerable, or lured into uncanny space. The spider attacks through illusion, poison, disguise, and entanglement rather than direct frontal force alone. Heroes must wound it first, then track it to the hidden nest where the true body waits. This pattern turns the encounter into an investigation of appearances, because what looks like monk, mansion, or woman may only be the outer web of the demon.