Senju Shinobi dies during the third Shinobi war and gets reincarnated as itama senju in the warring clans era with the skills Copy and devour. Also since it's his own skills he can't be controlled by the skills 
Copy: A copying ability that allows user to copy whole living or dead bodies and inorganic objects. The copied objects or copied people also completely copies all the abilities of the objects or people that was copied including chakra 
Devour: A ability that allows user to create a small black hole from there hand and just needs a small amount to absorb anything to gain its abilities, skills, techniques, appearance and chakra

Listening to Hashirama speak of his village—a place where children wouldn't have to fight, where clans could ally—Itama felt a profound sense of purpose. He had seen the future. He knew this dream *could* work, but also how fragile it would be. He decided he wouldn't just be a warrior. He would be the foundation's hidden architect.


Using his abilities, he began conceptualizing systems. From copied memories of efficient Senju craftsmen, he designed better infrastructure. From devoured scrolls on logistics, he formulated supply chain ideas. From his future knowledge, he drafted the basic concepts of a mission ranking system and a centralized academy. He hid these "ideas" as childish drawings and hypothetical questions to Tobirama, slowly planting the seeds of Konoha's institutions.


Chapter 14 - Hashirama’s Dream, Itama’s Blueprint