Ninja also employed a variety of weapons and tricks using gunpowder. Smoke bombs and firecrackers were widely used to aid an escape or create a diversion for an attack. They used timed fuses to delay explosions. Ōzutsu (cannons) they constructed could be used to launch fiery sparks as well as projectiles at a target. Small "bombs" called metsubushi (目潰し, "eye-closers") were filled with sand and sometimes metal dust. This sand would be carried in bamboo segments or in hollowed eggs and thrown at someone, the shell would crack, and the assailant would be blinded. Even land mines were constructed to use a mechanical fuse or a lit, oil-soaked string. Secrets of making desirable mixes of gunpowder were strictly guarded in many ninja clans.
Other forms of trickery were said to be used for escaping and combat. Ashiaro are wooden pads attached to the ninja's tabi (thick socks with a separate "toe" for bigger toe; used with sandals). The ashiaro would be carved to look like an animal's paw, or a child's foot, allowing the ninja to leave tracks that most likely would not be noticed.
A small ring worn on a ninja's finger called a shobo would be used for hand-to-hand combat. The shobo would have a small notch of wood used to hit assailant's pressure points for sharp pain, sometimes causing temporary paralysis. A suntetsu is very similar to a shobo. It could be a small oval shaped piece of wood affixed to the finger by a small strap. The suntetsu would be held against a finger on the palm-side and when the hand was thrust at an opponent using the longer piece of wood to target pressure points such as the solar plexus.
