Accidental Mark - Chapter 50

“Legend had it that in the deepest part of the oldest galaxy, there was a door as red as blood and fire.

Legends and myths, darkness and light, countless stories passed through this old door.

The Door of Constellation that overlooked everything would warn the sky and earth, sending darkness back to where it belonged.”

Pinnacle of martial, mountain shifting and sea filling, catching stars and seizing the moon, reverse the flow of time!

Extremity of the sword, one sword to form the dao, one sword to reach the immortals, one sword to break the laws!

The young Li Fuchen, chanced upon the Golden Talisman which allowed his spirit soul to constantly evolve. In this world where prodigies and experts were everywhere, he used the sword in his hand to ascend to the absolute pinnacle.

The world will decay one day, but my reverence shall be eternal.

- Description from Novelupdates

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?