Monster Paradise - Chapter 3: Goldfinger Has Been Activated

A skilled but unfortunate modern-day assassin was killed in a freak accident. However, he soon found himself summoned to another world by an evil wizard, who had him possess the body of a boy as an experiment. After successfully planning the evil wizard’s downfall, he used the wizard’s body as a springboard to gain influence and power in his new world.

- Description from Novelupdates

Long Fei, a cross-timer and doujin, is an otaku who traveled to another world. In the original world, he was an otaku fan of Gundam and military science fiction.

He died in an accident and was reincarnated into another world. The Gundam works he had read before his death and the techniques in various military novels could be brought to another world.

How would he use the Gundam that Long Fei created? What waves can be caused in this different world?

- Description from novelbuddy

I dedicated 10 years of my life, focusing solely on regression.[Authority: Death Regression has naturally been nullified.

Tangyuan was an excellent pulmonologist who, after an accidental death, acquired a system.By completing tasks in various fast-travel worlds, she would fulfill virtue and acquire a new life.The system chosen for her was the farming stream system, which included time-traveling through ancient times, the Republican era, apocalypse, modern times, and more.This fulfilled her joy of earning from nothing and also allowed her to enjoy the study of various professions within the fast-travel system.