
This process relates to the reincarnation of the souls of individuals who have passed away, playing the role of a vessel to host these souls, allowing the reincarnated individuals to battle once again.
How Did Tobirama Create Edo Tensei?
With the complexity and significant potential of Edo Tensei, many aspects of its creation and utilization reflect the essence of Tobirama’s character. As the Hokage, he developed this technique during the wartime period, amidst the ongoing conflicts among ninja clans.
In this context, it is logical that Tobirama would use wartime as a backdrop to refine Edo Tensei, a method that, while controversial, demonstrates his willingness to explore the limits of ninjutsu for military advantage.

Although the lore does not detail all the steps Tobirama took to develop this technique, it still leaves many distinct marks on the story.
On one hand, Tobirama is depicted as a visionary, responsible for many innovations that helped shape the foundation of the ninja world. On the other hand, some of his innovations, including Edo Tensei, raise significant ethical questions regarding the use of such power. Notably, this technique eventually became banned due to the moral implications and the potential for it to be used for malevolent purposes.
Through the creation of Edo Tensei, a completely different portrayal of Tobirama emerges, one who is willing to employ drastic measures in pursuit of security and stability for his people, even if that means breaching the established moral codes.