The new Impure World Reincarnation
The Impure World Reincarnation Jutsu in the original work is ultimately just a type of Earth Style technique, a resurrection Ninjutsu that combines Earth Style with Sealing Jutsu and Summoning Technique! Moreover, the person summoned by this Ninjutsu changes depending on the strength of the sacrifice used.
In the original work, the Chakra Impure World Reincarnation those resurrected using the Impure World Reincarnation technique is far inferior to that of their original selves! The Chakra of those summoned using this Impure World Reincarnation is drastically reduced. It's safe to say that the summoned individuals are absolutely no match for their original strength. Although the Impure World Reincarnation in the original work are also immortal, once they are shattered into pieces, their resurrection speed is very slow!
Although Kangetsu's modified Impure World Reincarnation is based on the same principle as the original, its essence has changed! First of all, Kangetsu referenced the ultimate Sealing Jutsu ' Human Body Seal ' obtained from the Uzumaki Clan, a Ninjutsu that can change a person's physique, making it more like the Ten-Tails ' physique!
The characteristics of this technique have been incorporated into the new Impure World Reincarnation. During the resurrection, a person's constitution is altered to match that of another person, and then the two are merged before being resurrected! In this case, the resurrected person will not only unleash their original strength but may even surpass it!
Another effect is the immortality. Because the ' Human Body Seal ' physique is biased towards the Ten-Tails, especially when Kangetsu used this Ninjutsu, she incorporated Tsunade's Yin Seal Ninjutsu from the original work, allowing Chakra to replace the immortality.
It can be said that as long as a person has Chakra, they are immortal. Even if their Chakra is exhausted, they will not die.
Because the remaining immortal body is the same as the Impure World Reincarnation in the original work. However, with each resurrection, the Chakra is essentially replenished. Since death after exhausting Chakra is equivalent to being resurrected once again, it can be described as a full-health resurrection!
As for Uchiha Izuna, he was resurrected using the modified ' Impure World Reincarnation ' technique by Kangetsu! First, the ' Human Body Seal ' Ninjutsu transformed Uchiha Izuna's physique into one more akin to the Ten-Tails, then he was merged into Uzumaki Ziyan's body, and finally resurrected!
When Uchiha Izuna was resurrected, he not only gained his original abilities, but also the abilities of the Uzumaki Clan, especially the physique of the Uzumaki Clan!
The Uzumaki, Senju, Hyuga, and Uchiha clans are all similar in constitution, so using members of these clans to revive Izuna has been very effective, especially the Hyuga. Because of the Sharingan and Byakugan, Izuna's eyes will likely be much stronger after his revival!
However, compared to the Hyuga Clan, Uzumaki Ziyan is now far stronger. After all, Uzumaki Ziyan absorbed the chakra of seven Tailed Beast, and his body still retains the Chakra of the seven Tailed Beast. Moreover, his physique has become even stronger due to the addition of the Tailed Beast. It can be said that Uchiha Izuna is now stronger than before!
Just like in the original story, after Uchiha Madara was resurrected, he obtained the abilities of Senju Hashirama, becoming even stronger. This is also a characteristic of Kangetsu's new Impure World Reincarnation!