Kunai

A kunai (くない) is an ancient kind of trowel, originated during the Tensho Era in Japan. The kunai was normally wrought of iron, not steel, cheaply forged and unpolished. The size of most kunai ranged from 20 cm to 60 cm, with the average at 40 cm. The kunai was used by common folk as multi-purpose gardening tools and by workers of stone and masonry. The kunai is not a knife, but something more akin to a wrecking bar. The blade was soft iron and unsharpened because the edges were used to smash plaster and wood, to dig holes and to pry. Normally only the tip would have been sharpened. The uses to which a kunai was put would have destroyed any heat-treated and sharpened tool like a knife.

Kunai normally had a leaf-shaped blade and a handle with a ring on the pommel for attaching a rope. This would allow the kunai to be strapped to a stick as an expedient spear, to be tied to the body as a hidden weapon, or to use as an anchor or piton of some kind.

Contrary to popular belief, they were not designed as throwing weapons, though they can definitely be thrown and cause damage. Ninjutsu is very versatile in the way it employs weapons and non-weapons. A ninja could work as a gardener during the day and use a kunai without raising suspicion.

Some images of actual kunai are available on The Virtual Museum of Traditional Japanese Arts webpage [1]

The Ninja weapon Kunai

A fictional kunai.

Just like with the shuriken and ninjutsu, the exaggeration persistent in ninja myths played a large role in creating the current pop culture image of kunai.

Currently, the kunai is commonly believed to be an ancient Japanese throwing knife. Designed as a weapon, larger than a shuriken offered increased accuracy, damage power and armour penetration when thrown, and could also be used in hand to hand combat more readily, and could even block sword blows. In addition, it could be used for climbing, as either a kind of grappling hook, or a piton.

The blade shaped like a squashed octahedron, a rod for the handle with a ring on the end, form an extremely simple yet effective design. It would be made of tempered steel, with sharpened edges, and polished to a shiny surface (For visual effect (metsubushi) or for aerodynamic abilities). Sometimes the clan symbol would be engraved on a side of the blade. The handle wrapped in fabric for better grip, sometimes with some strands hanging off the ring, to improve accuracy when thrown. (thus making it a kind of a throwing dart)

In Masaaki Hatsumi's Grandmaster of the Togakure Ryū school of Ninjutsu collection there are examples of short kunai, long kunai, narrow bladed types, saw-toothed types, and wide bladed types. In some cases, the kunai and the shikoro are hard if not impossible to distinguish. A shikoro is a wide bladed saw with a dagger-type handle.

Many ninja weapons were merely adapted farming tools, not unlike many of the weapons used by Xiaolin (Shaolin) Monks in China. It is not hard to realize why a kunai, which is a standard farming implement, became a useful weapon to ninja. Many of the ninja weapons, including the swords, were cheaply made, as the ninja did not need master-quality weapons to carry out their duties, but rather simply the quantity of weapons at their disposal. And since Kunai were cheaply produced farming tools of a decent size and weight, and could be easily sharpened, they fit the bill perfectly.

Kunai in modern pop culture

When kunai appears in modern works of fiction, it is usually described as purposefully designed with military use in mind, often resulting in a weapon with superior qualities, used almost exclusively by Ninja/Thief type characters.

• The undead ninja Scorpion (Mortal Kombat) uses a kunai attached to the end of a rope, which he tosses at his opponent and if it connects, he pulls the foe toward him, yelling "GET OVER HERE!" or "COME HERE!".
• In Tecmo's Ninja Gaiden title for the Microsoft Xbox, the ninja Ryu Hayabusa uses what appear to be kunai as throwing stars, and can clearly be seen sheathing them in a scene near the beginning of the game.
• In Final Fantasy XI, the only usable Ninja Weapon at Level 1 is the kunai.
• In Final Fantasy Tactics Advance, kunais are mission items, though translated as "Ninja Knife."
• In the manga of Fullmetal Alchemist, the female ninja, Ran Fan, uses kunai as her primary weapon.
• In the ninja themed manga/anime Naruto, kunai are very common hand-to-hand and throwing weapons. They also differentiate in various sizes and shapes, ranging from small throwing knives, gigantic, double-bladed, standard straight blades to curved and scalpel-like kunai.
• In the video game Suikoden 5, a character named Sagiri uses a kunai as her weapon.
• Kunai is available as a weapon type in Soul Calibur III, used by the character Greed and any player-created ninja class characters.
• In Darkest Age, wielding the kunai gives you exceptional flipping ability and style points.
• In The Fourth Coming a Djinn uses three kunai until reaching the ninth level of power, where he then upgrades to the tuning shovel.
• Espio the Chameleon from the Sonic the Hedgehog series uses these as one of his weapons.
• In the manga/anime Rurouni Kenshin, the ninja girl Machimaki Misao uses kunai as her primary weapons, throwing them in her ultimate attack, "Kansatsu Tobikunai" or "Killing Flying Daggers."
• In the live-action Japanese series Kamen Rider Kabuto, Kabuto's main weapons is the "Kunai Gun," which is a transforming kunai/gun weapon which can be stabbed into an enemy to finish them off. This technique is called the "Avalanche Slash."
• In the MMORPG MapleStory, one type of throwing star weapon available to the player looks very similar to the kunai. These stars, known as "Steely throwing stars" in the game, are one of the best, providing good damage power and ability to carry more stars than with other types; the distinctive look is also a factor, making the Steely a very valuable and sought after item.
• In the Mega Man Zero series, Phantom uses kunai.
• In the Mega Man ZX series, model PX uses kunai.
• In the game Tenchu: Fatal Shadows for the Sony PlayStation 2, both Ayame and Rin use kunai as a basic throwing weapon.
• In the video game Shinobi, The main character, Hotsuma, can use a kunai as one of his weapons.
• In the movie Hrafninn flýgur, a kunai is used by the main character.
• The mechanical robot ninja Sasuke from the Ganbare Goemon series uses two Kunai to slice enemies (normally) in half.
• In Yu-Gi-Oh!, both the manga/anime and the card game, Kunai with chain is a card which boosts a monster's attack power. It is notably used by Katsuya Jonouchi a.k.a. Joey Wheeler. It should be noted, that it resembles a kusari-gama instead of a 'Kunai with chain'.