Katsuyu: Immense Network Healing is a cooperation ninjutsu used by Katsuyu and its summoner using the link shared via the Strength of a Hundred Seal.[3]
Usage
Firstly, Katsuyu divides its body into several smaller clones, and then each attaches itself to a person. The slug's summoner then channels their medical chakra through Katsuyu, who in turn transfers it to the wounded person, healing their wounds, restoring their stamina and chakra reserves.[1]
This technique allows the user to heal a great number of persons simultaneously regardless of distance. While using this technique, the user is linked with Katsuyu, shown when Tsunade was able to communicate directly with the slug, had a sense of what Katsuyu was encountering on the battlefield, her reaction to Katsuyu finding Kakashi Hatake apparently dead,[4] and later when she told Chōji Akimichi that his father was still alive after a brief pause.[5]