Meidō Zangetsuha

The is a technique that creates a path that sends anyone who is hit with it directly to  hell, killing them without actually harming them. The technique originally belonged to the yokai Shishinki. The Great Dog Demon battled Shishinki and defeated him with the Tessaiga and used it to steal the technique. Because of the techniques dangerous ablitiy the Tenseiga was created to contain it.

The Meidō Zangetsuha creates a massive black circle that will send a entire body into hell, leaving no trace left behind. However when one is first learning to use the technique the Meidō will take the form of a black cresent moon that will only send a part of person into hell along with their soul, stronger yokai may be uneffected by the cresent Meidou. As the user gains strength, the Meidō will grow until it becomes a perfect circle. When Totosai unlocked the technique in Tenseiga, Sesshomaru could create a cresent-shaped Meidō.

As Sesshomaru gained strength, the Meidō became bigger, than became a oval shape, and finally a perfect circle. Sesshomaru gave the Meidō Zangetsuha to InuYasha by allowing Tessaiga to absorb it.

When InuYasha mastered the Meidō Zangetsuha, the technique evolved into a new technique that matched Tessaiga's nature of a sword that cuts. The new Meidō takes the form of a blade that can cut opponents and send their remains to hell. The new Meidō gains the ablitiy to cut, while keeping its original power intact, allowing it to even affect beings that have previously been shown to be completely immune to the regular Meidō, although the Shikon no Tama was able to survive even this technique's strength.