Chakra is kneaded within the body and then changed into special chemical substances which is then ejected through the mouth. When this substance comes in contact with the air outside the body, it instantly changes and is transformed into a mist of deadly poison. The poison's ability to kill is tremendous, as even just breathing in a small amount will mean the end of the target's life. As this technique combines ninjutsu, chemistry, and medical knowledge, using it requires fine chakra control and advanced ability in medical ninjutsu.
Ibuse used a variation where it causes the target's body to go numb in a matter of seconds after inhalation, rather than cause instant death as with Shizune's usage. With the targets paralysed, Hanzō can attack at his leisure. This poison, however, must first be generated and stored for five minutes within Ibuse's body before using this technique.