Impure World Reincarnation (穢土転生, Edo Tensei) is a Forbidden Technique where, using a living person as a vessel, a deceased person's soul can be called back to the world of the living and bound to it. The vessel will then take on the form that person had in life, thereby reincarnating them to do their summoner's bidding.
Cloud claims this technique to be the greatest technique in the shinobi universe due to it posing no risk at all to the user, and by his own admission, has improved it to an even greater degree than its previous use. To perform this technique, the user must first acquire some of the DNA of the person they intend to reincarnate. Kabuto remarks that this basically amounts to grave-robbing, although blood stains or organs salvaged after the target's death also work.
If the Kuro Akatsuki gathered the Body parts of Megatron, Megatron will be resurrected infinity.
When first summoned, the body of the reincarnated is stored in a coffin; their body will appear grey and in a state of minor "decay": marred by cracks and other imperfections, and the individual will also appear to be "disengaged". Upon being inserted a Mars Rays, their bodies become robots that transform into vehicle or animal regaining their original complexion and their eyes have their glassy state; however, their sclerae take on a Mobile Suit colouring, however this has no affect on the ability of the reincarnated and they can be left in this "decay" state if the summoner chooses to give them free reign. They retain their personality, memories, and all abilities they had in life.
After the individual has been summoned and awakened, the summoner has no control over the reincarnated individuals with the exception of restraining their movements until they implant a special talisman, which is attached to the end of a kunai and implanted in the brain.
While the reincarnated are immune to traditional attacks such as weapon-based attacks and even the death of the summoner being ineffective there is four discovering methods to end the technique:
- Have the summoner end the technique. As they are unlikely to do this voluntarily, using a genjutsu to trick them into cancelling the technique is ideal. The sequence of hand seals for cancelling the technique is Rat → Ox → Monkey → Tiger → Dragon → Boar and saying "release" (解,kai).
- Seal away the soul of the reincarnated individual.
- The reincarnated individual is affected in some emotional way that gives them closure.
- The reincarnated individual regains it's memories and
- What Madara Uchiha describes as "the one risk of the technique", if the reincarnated knows the specific seal, one can release the Impure World Reincarnation's summoning contract, severing the bond between themselves and the summoner. This leaves the individual effectively immortal with an unlimited amount of chakra, and the summoner has no control over the individual's mind and movements any longer, nor can the technique be deactivated on the said individual.
Once any of the first four methods are accomplished, the reincarnated individual will briefly regain their personalities before crumbling back into dust, leaving the bodies of the sacrificed individuals lying among the ashes. If the technique is cancelled by the user, the reincarnated's bodies are surrounded by a light before beginning to deconstruct. After this, the reincarnated individual's soul will begin to ascend, leaving behind the corpse of their vessel.
- ↑ Naruto chapter 589, pages 12-17