The bo'tous spore functioned as a bio-weapon engineered by the Yuuzhan Vong. It resided within the respiratory system of a carrier, enabling them to release the spores through exhalation when near a designated victim. Upon exposure to the atmosphere, these spores transformed into bo'tous. An adept individual had the capacity to transport four units of bo'tous spore. The sole recorded instance of bo'tous spores being deployed occurred in 25 ABY, specifically when the priestess Elan endeavored to murder a number of Jedi Knights by pretending to abandon her allegiance and join the New Republic.