Yin-Yang Harmony System - Chapter 50

Chen Minhao found himself transmigrated to a parallel world in China, and he even became an idol trainee. By virtue of his efforts in mastering his IQ, EQ, and his looks as his weapons, he became a celebrity with a huge fan base step by step, and ultimately became a global superstar that conquered the both the fields of acting and singing.

- Description from Novelupdates

My name is Xu Yi. I was lucky to acquire the Survival System, which allows me to receive various high-tech gift packages just by checking in every day. While others face survival challenges in the wilderness, for me, it's like going on vacation.

In 1177 Jerusalem, Ethan Caldwell awakens as the leper king Baldwin IV, blending modern ingenuity with medieval valor. Introducing hwachas, windmills, and a revolutionary crossbow, he leads a crusade to conquer the Sinai, outwitting Saladin and transforming the Crusader states.

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?