The Shikomizue is a type of Japanese staff traditionally used as a concealed weapon. Its unique design incorporates a katana blade or short sword inside, allowing the staff to transform into a lethal weapon with one quick movement. Originating in the Edo period, the Shikomizue was popular among samurai and rōnin who needed to conceal their weapon in public places where carrying a sword was prohibited. This ingenious combination of gun and staff offered a surprising tactical advantage in combat or self-defense situations.