Ōmukade

Also Known As: 大百足, “giant centipede”; the centipede of Mount Mikami
Region/Culture: East Asia
Mythos: Japanese Mythology
Primary Type/Nature: Monsters and Beasts
Mythical Attributes: Its shell turns arrows, its venom is deadly beyond any natural centipede’s, and it hunts serpents and dragons as readily as it hunts men.
Role in Mythos: The ōmukade is the monster of the Tawara Tōda legend, the mountain-dwelling predator that terrorises the dragon king’s household in Lake Biwa until the archer Fujiwara no Hidesato kills it.
Relation to Humans: It is a mountain thing rather than a village one, and people meet it only when it comes down to feed, at which point ordinary weapons are useless against it. Killing one has always been work for a warrior, and the one warrior who managed it did so with an arrow he had spat on.

Torchlight came down Mount Mikami in the dark, two or three thousand flames swinging along in a single line, and the men watching from the lakeshore understood a little too late that nobody was carrying them. The lights were legs.

What they belonged to had been on that mountain long enough to be a fact of local life, the way a bad stretch of road is a fact. Popular tradition, written into an Ōmi guidebook by the eighteenth century, has it coiled around Mikami seven and a half times, which is less a measurement than an admission that nobody wanted to get close enough to count. The older tale is more restrained and more unpleasant. It gives the creature a head like a gyūki, an ox-demon, set on a body that no arrow could open, and it gives that body an appetite that had already worked its way through the beasts of the mountain and the fish of the lake.

The seed of it is a real animal, and anyone who has lived in a Japanese house knows the seed. Mukade grow to the length of a hand, black-green and segmented, with a burnt-orange head and legs that ripple in sequence when they run. They come in under floorboards in the damp months, they turn up in bedding, and their bite is a genuine, memorable pain. Scale that up until the segments are the width of a road and the fangs are the size of anchors, and the folklore has done nothing except remove the ceiling.

Where it came from, the record does not say. There is no birth story for the ōmukade, no curse that produced it, no god who made it as a punishment. It simply lives in the mountains and the caves, in dark humid places large enough to hold it, and the stories are content to leave the question alone. What they insist on instead is diet, and this is the strange part: the ōmukade eats dragons. In a mythology that puts dragons at the top of the water and the weather and much of the Buddhist cosmos, here is a bug that treats them as livestock.

Which is how the trouble started. Night after night the thing came down to Lake Biwa and fed on the dragon king’s household, on his subjects and his kin, until the dragons who ruled the water were reduced to the position of villagers waiting for a raid.

The relief came in the person of Fujiwara no Hidesato, an archer of the tenth century whose reputation later grew a legend the way a hull grows barnacles. He arrived at Seta Bridge to find an enormous serpent lying across it, twelve-horned and by one account two hundred feet long, and the local people gathered at a safe distance because nobody would cross. Hidesato walked up its back. Scales gave under his sandals with the sound of dry tiles. He reached the far side without looking round and carried on.

That night a woman came to him and said the serpent had been her. She was of the dragon palace beneath the lake, she said, and she had lain on the bridge for days precisely to find someone who would not run, because her family were being eaten and none of them could stop it. Then she told him where to stand.

He stood at Seta and watched the torches come down. His first arrow struck the shell and glanced off. So did the second. With one arrow left he put it to his mouth, wet the head with his own spit, spoke the name of Hachiman, and shot. This time the point went in. The creature came apart on the slope and he finished it with his sword.

The dragon woman’s gratitude took the form of objects that do not run out: a bag of rice that stayed full however much was taken from it, a bolt of silk that never shortened, a cooking pot that produced food without a fire. The rice bag is why he is remembered as Tawara Tōda, Rice-bag Tōda, a nickname built on a pun. He was taken down to the dragon palace and sent back up with armour, a sword and a great bronze bell, and the bell he gave to Mii-dera at the foot of Mount Hiei, where a further legend later attached itself to it.

The story did not arrive in one piece. The oldest surviving version sits in the fourteenth-century Taiheiki, and there the dragon comes to Hidesato not as a beautiful woman but as an odd small man in a court cap, the hero is entertained in the palace first and fights the centipede afterwards, and there is no magic pot, only the bell. The lady, the Buddhist dragon king Sāgara, the layered miracles and the pun on the rice bag all belong to the later Tale of Tawara Tōda, which circulated in painted scrolls and cheap woodblock books through the seventeenth century and made the episode famous. The seven and a half coils came later still. The monster grew in the retelling, as monsters do.

Its powers are all one power, elaborated. It is armoured past the point where weapons matter, strong enough to take dragons out of their own lake, venomous, and large enough that its approach is mistaken for an army with lights. Nothing about it is subtle and nothing about it needs to be.

Its weakness is one of the odder specifics in Japanese folklore. Human saliva is poison to it, and a blade or an arrowhead wet with spit will go through the shell that turned everything else. No source explains why spit works. The tale simply hands the hero the one substance he is guaranteed to have on him at the top of a mountain with no arrows left, and lets him ruin the invulnerable thing with it.

Frequently Asked Questions

What is the Ōmukade?

The Ōmukade is a giant centipede from Japanese folklore, a mountain-dwelling monster whose name means “giant centipede.” It is famous for an armoured shell that ordinary arrows and blades cannot pierce, and for preying on serpents and dragons as well as people. Its best-known appearance is in the legend of Fujiwara no Hidesato and the dragon king of Lake Biwa.

How was the Ōmukade killed?

Fujiwara no Hidesato killed the Ōmukade with a bow at Seta, near Lake Biwa. His first two arrows glanced off the creature’s shell, so he coated the head of his third and last arrow with his own saliva and prayed to Hachiman before shooting. That arrow pierced the shell, and Hidesato finished the wounded creature with his sword.

Why is human saliva the Ōmukade’s weakness?

Human saliva is simply toxic to the Ōmukade in the tradition, and no surviving version of the story explains the reason. A weapon wet with spit can penetrate the shell that stops everything else. It is the detail on which the entire Tawara Tōda legend turns.

Where did the Ōmukade live?

The Ōmukade of the legend lived on Mount Mikami, near Lake Biwa in what is now Shiga Prefecture, and popular tradition describes it coiled seven and a half times around the mountain. More generally, ōmukade are said to inhabit mountains and caves and any dark, humid place large enough to hold them. The Mikami creature came down at night to feed on the dragon king’s kin in the lake below.

What rewards did Fujiwara no Hidesato receive for killing the Ōmukade?

The dragon woman gave Hidesato a bag of rice that never emptied, a bolt of silk that never ran short, and a cooking pot that made food without fire. The inexhaustible rice bag is the origin of his nickname Tawara Tōda, meaning Rice-bag Tōda. He was also entertained at the dragon palace beneath Lake Biwa and given armour, a sword and a great bell, which he donated to the temple of Mii-dera.