the Jitsutyr was a tan paste refined from the venom of the jitsutyr, a large clam native to cold freshwater lakes, closely related to the jitsu, despised as a dangerous pest by fishermen. Jitsutyr was prepared by immersing the clams in hot salt water, inducing them to secrete the oily venom as a protective measure. Some of the oil floated to the surface, where it was collected. The oil was then boiled in vegetable oil with flowers of sulfur and finely ground charcoal. The sticky jitsutyr paste collected on the container's walls. Jitsutyr killed by destroying the victim's lungs.