MTL - Poison Genius Consort - Chapter 1009 Is this feeling?

Xia Yan passed through to the world of Bleach and became an eleven-year-old boy. He was rescued by Renji and Rukia in the Seireitei, and he was studying at Shin’ō Academy, and he was a student of the same class.
He is a top student of the Shin’ō Academy, and he is vying for strength by various teams. In the end, he has entered the first team of secret mobile maneuvers.
He will use punishment to kill every person who tries to threaten the martyrdom and protect his loved one.

- Description from Novelupdates

This is a story about the protagonist getting the system, going crazy in the biochemical apocalypse, producing aircraft and tanks, destroying zombies, saving good people and killing bad people.

- Description from novelbuddy

In an era when the power of Fire Magic was considered to have reached its limit, one girl began researching nuclear fusion.

It was understood that this was a capitalist country, where the possession of the greatest amount of capital determined to whom the nation effectively belonged.The smile that had been resting on William Sheffield’s face was abruptly erased as his expression turned cold. In a tone laced with determination, it was demanded by him that the police be contacted immediately so that they could crush those who stood in their way. The reasoning behind his words seemed clear: if such actions had been taken before by someone like Rockefeller, then why should it not also be possible for Sheffield?A sense of irony hung in the air as the sentiment was expressed—this was America, where each day seemed to unfold as though it were part of an ongoing shootout, with battles fought not just with guns but with power, influence, and wealth.