It may be an ancient tradition in the rain forests of Borneo thousands of miles away, but now blow darting is finding a new home among the pensioners of Japan.
Here in Tokyo's concrete jungle, the 600 retirees battling it out for blow dart supremacy are part of a growing trend among the country's elderly.
In just five years the country's blowgun club has trebled in size, and is on target to hit 30,000 members.
The average age is a venerable 70-years-old.
Blow dart instructor Nobuhiko Yamada says this boom among the grey generation is down to blow darting's simple secret weapon.
"Old people are really getting into it because it's easy for anyone to do - whether your legs are playing up, you're confined to a wheelchair, or missing an arm. In fact you can do it even if you've got no arms. It's just that single puff of air," said Yamada. "When they find out that there is a sport such as this one, which is fun and ideal for the elderly, they become hooked."
The meditative movements of this sport, called 'fukiya' in Japanese, have all the feel of the country's traditional martial arts.
Japanese popular culture places blowguns in the world of ninjas and nighttime assassinations, although historical records are few.
But the blow darting that these elderly people enjoy was created in 1998 -- by a retired Japanese man looking to liven up his daily breathing exercises.
The old age pensioners gather in a gymnasium. They put plastic darts -- with blunted tips -- into hollow poles and shoot darts at a target.
"Well, blow darting's different because you can do it at a pace that suits your own body. It's down to the individual, it's not a group activity," said 79-year-old Yoko Onmyoji.
By 2060, the number of people aged 65 or older in Japan is expected to rise to 35 million, accounting for nearly 40 percent of the population, as compared with 23 percent in 2010.