Shuriken (Small Throwing Blade) (手裏剣)

A shuriken is a small weapon shaped like a sword or needle, thrown at an opponent to diminish the fighting power of an enemy. They are widely known as a weapon used by ninja (professional spies in feudal Japan highly trained in stealth and secrecy). They are also known as token (throwing swords), shuriken (手離剣, or throwing blades), small throwing blades, shooting stars, and small throwing blades.

It is also a method of origami (paper folding) for these weapons.

Summary

There had long been methods of escaping danger or hurting an enemy by throwing weapons at them, but the weapons used were tsubute (throwing stones), short swords, uchine (throwing arrows), uchiya (throwing arrows), and needles among other weapons. Short swords and uchine were somewhat costly and unsuitable for repeated use, uchiya were too bulky to bring along, and needles were inexpensive but lacked force. It was in the late Muromachi period that shuriken appeared in the form known today as an affordable weapon specifically for throwing, free of these disadvantages. It is believed that not only the shape, but also the word shuriken became established during this period.

The character 裏 means both 'back' and 'inside,' but the 裏 in shuriken (手裏剣) does not mean back as in 'front/back,' but inside as in 'outside/inside' seen in the word uchiura (内裏). It was sometime written as 手離剣, since the sword hidden in one's hand is released from the hand and hits the enemy.

The technique of using shuriken is sometimes included in the Bugei Juhappan (18 skills of martial arts), but unlike swordplay, it could be used for assassination using poison, and thus did not prosper much as a military art performed openly.

Since it is a technique where an object at hand can be substituted for toteki (throwing), it can be used today for self-defense.
However, it is likely that the use of such lethal weapons prepared for self-defense may not be considered 'self-defense,' and if one kills a criminal using this, you may prosecuted for 'homicide by willful negligence' or 'manslaughter.'
In addition, the possession of shuriken alone may be in breach of the Sword and Firearms Control Law or the Minor Offense Act.

Through their depiction in period dramas, it is often misunderstood that among Japanese swords, kozuka (the hilt of a small sword or the small sword itself) and kogai (a spatula attached to a small sword), which were stored in the scabbard as an accouterment of uchigatana and short swords, were weapons used as shuriken in emergencies. However, a kozuka is a single-edged knife for daily use, and a kogai is a spatula for fixing hair, and it is extremely difficult to throw them as a shuriken since the center of gravity is unadjusted and its strength is inadequate. Some say it was actually long swords that were thrown.

Shape

Shuriken can be divided broadly into two types, kurumaken (wheel shuriken) and bo shuriken (stick shuriken). Kurumaken have blades placed on a cross-shaped or fylfot-shaped iron plate, and bo shuriken are small sticks made of iron with one or two ends sharpened.

Kurumaken stabilize while spinning in the air during toteki, so the accuracy of hitting the target can improve after a relatively short period of training. On the other hand, a disadvantage is that the sound they generate when spinning makes it easier to be noticed by the target, and that it is inconvenient to carry along. Additionally, since it does not pierce deep into the target, it is not effective enough in killing or wounding an enemy, but sometimes such weakness is offset by applying poison to the blade. Copper alloy may be used on the blade for this purpose. According to the number of blades pointing radially, they are called sealed cross blades, roppoken (six-blade shuriken), happoken (eight-blade shuriken), and ten-blade shuriken among other types.

In society in general, and in the media, the word 'shuriken' often paints an image of kurumaken, but this is probably because the shape resonates in the popular imagination. The shuriken in origami also has this kurumaken shape.

The bo shuriken is a simply-shaped weapon, but the length, and center of gravity among other factors vary according to the school. It overcomes the weaknesses of kurumaken such as regarding portability, the power to kill and wound, and the sound when thrown, but requires a more advanced toteki skill. In order to make it easy to carry, there are pairs of bo shuriken with blades on both sides, secured in the middle like scissors, to close into the shape of a stick when carried and open into a cross when used. The Negishi-ryu school uses a heavy shuriken with the center of gravity at the front, aimed at stabilizing the flight of the weapon, as well as increasing its force.

Depending on the practitioner, various things can be used as 'shuriken,' such as the shuriken 'hyo' (also known as Chinese-style), which is shaped like an arrowhead, or unusually heavy and huge shuriken.

Throwing techniques

The word 'strike' is used instead of 'throw' for shuriken, but writers may use 'throw' in novels out of consideration that it is not a common expression. Additionally, 'striking with a shuriken' is also described as daken (striking knife). As an example, in the case of bo shuriken, there are three major techniques for daken.

The chokudaho (direct throwing technique)
Position in a way such that the pointed end faces up. This is a method of toteki where after leaving the hand, the pointed end stays directed towards the target during flight. It does not fly straight, but instead flies in an arc as of the slashing movement of a sword.

The hantendaho (half rotated throwing technique)
This is a method of toteki where the pointed end is held in the opposite direction and the sword is inverted at the moment of striking, flying in the same way as the 'chokudaho.'
It strikes in this inverted position and does not spin.

The kaitendaho (spinning method)
This is a method of toteki where after leaving the hand, the weapon spins until it hits the target.

This method of toteki is common for kurumaken and knife throwing in the West, and in the toteki of kurumaken a movement as of spinning a sword is necessary. It is a multiple spinning method used to increase force and improve accuracy. In the case of large sealed cross blades, in one method of toteki one grasps one of the swords with a finger placed on the other sword, and the sword is made to spin by striking it in a hammering motion.

Meanwhile, in knife throwing the target is hit by adjusting the speed of the throw and the way it spins and depending on the distance from the target.

Among Japanese shuriken techniques, the 'chokudaho' is the most basic way of daken, but it is a unique technique from an international standpoint.

Combat techniques using shuriken

According to one technique, shuriken are used as camouflaged weapons or smaller weapons for combat. Its use as a camouflaged weapon was not widespread, but was passed down as a hidden, secret technique in judo (a Japanese art of self-defense), and swordplay among others, and therefore the names and usage vary according to the school. One school calls it the hidden sword technique, and the school practices attacking stealthily, attacking mainly the vital parts of the body such as the neck, throat, chest, the pit of the stomach, and the backbone (spinal cord). Additionally, the ura (back) of shuriken is for combat, while the omote (front) is used for daken (methods for toteki at the opponent).

Shuriken as a sport

Recently, organizations have emerged focusing on enjoying shuriken as a sport.

The image of shuriken used by ninja

Scenes where multiple shuriken are thrown one after the other, or are used as a method of attack to kill or injure an enemy are common in ninja cartoons and movies, but the main purpose of the weapons and tools for ninja are basically to 'gain time for escape' and they were not commonly used to actively provoke a fight. Additionally, the main goal of the ninja is not to fight, but to 'gain information (or spread misinformation) and return safely,' corresponding to today's secret agents or covert special mobile units, and such scenes as those where the characters bring around bulky iron pieces of shuriken and throw them one after another are unrealistic. In reality, they carried one or two for an emergency escape, or one bo shuriken to be used as a tool to climb stone walls and dig holes. Shuriken, the use of which was taught at dojo (halls used for martial arts training) as a 'martial art,' and the shuriken which ninja carried following its original use, should be treated as separate things.

Shuriken as play equipment
They appear as children's toys, as weapons used by a mysterious group called ninja.

Many are made of hollow plastic with safety in mind, and since they can be folded into origami, they have become a plaything for children.

Shuriken in origami

The shuriken is created by folding two origami papers into the form of an actual shuriken. They can also be used as playthings for children for ninja-gokko (childhood ninja games) among others.