A shinobi is a covert agent in feudal Japan. Functions include espionage, sabotage, infiltration, and assassination. With the aid of a disguise, a ninja could gather information without being spotted. A primary practice of vandalism is arson, in which a ninja would set a camp or castle on fire. Most ninjutsu techniques revolve around ways to avoid detections, as well as methods of escape. These skills are loosely grouped under corresponding elements. A few examples are Hitsuke, Tanuki, Ukigusa, and Uzura; Hitsuke distracts guards by starting a fire (katon) away from a shinobi’s point of entry, Tanuki camoflauges oneself within foliage (mokuton), Ukigusa is the practice of throwing duckweed over water (suiton) to conceal underwater movement, and Uzura curls users in a ball and makes them motionless so that they appear as stones (doton).
Ninjas, by Aleksey Bayura.