Izanami

Izanami is one of the ultimate dōjutsu of the Uchiha clan. This technique affects targets through physical sensations shared with the target. Like its counterpart Izanagi, in exchange for the temporary ability that it grants the user, the Sharingan with which Izanami is cast is sealed away and loses its light forever. According to Itachi, this technique and Izanagi form a pair, but unlike the latter, which is a technique capable of altering destiny, Izanami is instead one that "decides" it.

To begin the technique, the caster must voluntarily decide to act, while the Sharingan is used to memorise the bodily sensation of that instant like a photograph (represented as: A). The user must then replicate the same sensation intentionally while using the Sharingan to memorise that instant as well (represented as: A'). Izanami then overlaps the two identical bodily sensations (A and A'), creating a loop. The flow of time and events that occurs between the two memorised sensations will replay in an infinite loop. Despite being able to become consciously aware of their situation, the victim is unable to significantly alter or escape from the inevitable progression of these events, except by acknowledging the results of what they have done and stop trying to run away. Whilst under the effects of the technique, the target will stand motionlessly as the loop of events continually replays inside their mind. Because this technique was created as a counter to Izanagi, the victim is able to escape the infinite loop by simply accepting their fate.

Creation
According to Itachi, there was a point in time where members of the clan abused the abilities granted by Izanagi and would simply cast the technique as a means of escaping undesirable results of their actions. Thus Izanami was created as a method to punish the clansmen, as well as save them from their arrogance. By imprisoning them within an unalterable loop of events, the victim must accept the reality they had created if they ever wish to escape the illusion.

Influence
Like the various techniques used with the Sharingan, this technique is named after a Shintō goddess. In this case, it is Izanami, who, together with her brother and husband Izanagi, created the islands and other deities of Japan.

One of the most famous stories about Izanami tells the tale of how Izanagi goes into Yomi, the Japanese underworld, to retrieve her after she died giving birth to the Shintō fire god, Kagutsuchi. In Yomi, he manages to get Izanami and they both try to leave, however, Izanagi was not supposed to look at her before they escape. Right before they reach the exit, Izanagi looks back and sees her in a decayed form. Frightened, Izanagi flees from Yomi and blocks the cave. Izanami curses Izanagi saying that she will kill 1000 people per day. In response, Izanagi says that 1500 people will be born each day. In another variation of the story, it is stated that Izanami told Izanagi to leave, however, he came back while she slept and lit a fire that revealed her decayed form, prompting him to escape out of fright, and barricade her inside with a giant boulder.