Tools of a dying art
Japan's era of shoguns and samurai is long over, but the country does have one, or maybe two, surviving ninjas. Experts in the dark arts of espionage and silent assassination, ninjas passed skills from father to son - but today's say they will be the last.
Japan's ninjas were all about mystery. Hired by noble samurai warriors to spy, sabotage and kill, their dark outfits usually covered everything but their eyes, leaving them virtually invisible in shadow - until they struck.
Using weapons such as shuriken, a sharpened star-shaped projectile, and the fukiya blowpipe, they were silent but deadly. Ninjas were also famed swordsmen. They used their weapons not just to kill but to help them climb stone walls, to sneak into a castle or observe their enemies.
Most of their missions were secret so there are very few official documents detailing their activities. Their tools and methods were passed down for generations by word of mouth.
This has allowed filmmakers, novelists and comic artists to use their wildest imagination.
Hollywood movies such as Enter the Ninja and American Ninja portray them as superhumans who could run on water or disappear in the blink of an eye.
"That is impossible because no matter how much you train, ninjas were people," laughs Jinichi Kawakami, Japan's last ninja grandmaster, according to the Iga-ryu ninja museum.
However, ninjas did apparently have floats that enabled them move across water in a standing position.
Kawakami is the 21st head of the Ban family, one of 53 that made up the Koka ninja clan. He started learning ninjutsu (ninja techniques) when he was six, from his master, Masazo Ishida.
"I thought we were just playing and didn't think I was learning ninjutsu," he says.
"I even wondered if he was training me to be a thief because he taught me how to walk quietly and how to break into a house."
Other skills that he mastered include making explosives and mixing medicines.
"I can still mix some herbs to create poison which doesn't necessarily kill but can make one believe that they have a contagious disease," he says. Kawakami inherited the clan's ancient scrolls when he was 18. While it was common for these skills to be passed down from father to son, many young men were also adopted into the ninja clans.
There were at least 49 of these but Mr Kawakami's Koka clan and the neighbouring Iga clan remain two of the most famous thanks to their work for powerful feudal lords such as Ieyasu Tokugawa - who united Japan after centuries of civil wars when he won the Battle of Sekigahara in 1600.
It is during the Tokugawa era - known as Edo - when official documents make brief references to ninjas' activities.
"They weren't just killers like some people believe from the movies," says Kawakami.
In fact, they had day jobs. "Because you cannot make a living being a ninja," he laughs.
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