A special weapon with a sharp curved blade adorning one end of the shaft, and a chain the other, at the end of which is a metal weight. It was the favourite weapon of Shisenin Kosen, a warrior who trained in the mountains and is said to have mastered the 100 martial disciplines. He made several improvements to the weapon himself. Kosen was one of the Shishido, a powerful mountain clan from Aki province, and caused endless trouble for the daimyo Mohri Motonari. The two later joined forces after the Battle of Itsukushima.