OMG! I Transmigrated into Four Books at the Same Time! - Chapter 92 - 89: This Works?

Young and skilled warrior Jincheon finds himself at the heart of chaos when his hometown is suddenly attacked. Amid brutal and deadly battles, he faces an impossible choice – life or death.Surrounded by the flashing, glowing swords of his bodyguards and the shadows of the attackers, Jincheon desperately searches for an escape, only to realize that in this world, there are no easy answers. As he tries to flee through the kitchen of a small, strange, and unusually dark inn, he discovers an even greater danger: the exit is hidden, and the only way out is through a dirty, old drain.But his path is not so simple. Along the way, he encounters a mysterious man whose intentions remain unclear, but who seems to know exactly how to help Jincheon. With time running out and death looming ever closer, Jincheon must decide whether to trust this stranger or face even greater dangers alone.How far is he willing to go to survive? And who will turn out to be an ally, and who an enemy, when every step is a battle between life and death?

Roy’s life was nothing special. The only thing commendable was the last few moments when he saved a mother and her child from a drunk driver.
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It’s really an egg! Damn it, what kind of monster have I become? Did I fall into Hell instead of making it to Heaven??
Join Roy as he ventures through various worlds with the Custom Made Demon King System—a system that allows Roy to draw anything he can imagine and create it through exchanging souls!

Earth’s top weapon specialist’s soul crossed over to an alternate world, merged with Rebirth Martial Emperor’s memories, cultivating Nine Dragons War Sovereign Technique, sweeping through all opposition with invincible might!

Able to refine medicine, capable of crafting weapons, and knows the art of inscription….

Being skilled in all professions is the way of kings!

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?