Munitions Empire - Chapter 821 - 765 new weapons are too many

A lecherous army special task force soldier from 21st-century Hong Kong is selected to travel back in time, choosing to go to the Chinese Warring States Period. Unfortunately, the time machine runs into an error during the experiment. With no foreseeable way to return to the present, he must use his combat skills and knowledge of history to thrive in his new life in the year 251 BC.

I woke up in my sleep, and a strange door appeared in my home…Behind every door is a strange world.

In the nightmare world, Jiang Cheng added the news from the strong man to the fat man, and he almost cried when he heard the latter, “If you die here, the whole family will stand upside down and bleed?”

“Is such that.”

“Then I don’t think you are too scared?” The fat man widened his eyes.

Jiang Cheng turned his head and said in a very formal tone: “Because I am an orphan.”

- Description from novelbuddy

For unknown reasons, he finds himself transported to a parallel world's Japan, unexpectedly taking over the body of a soon-to-be high school student who had died accidentally. Surprisingly, he did not inherit any memories. However, the first challenge he faces upon arriving here is a language barrier...Just as he struggles to communicate with his new family, a heavenly voice arrives: the black technology system has been activated, and the initial item—translation konjac—has been distributed.This is the story of someone with above-average intelligence but almost no physical strength in the Classroom of the Supreme Power.