Supreme Star Card Master - Chapter 543 - 451: Arrow Breaks the Lion

A scientific genius named Thomas Harrier was transmigrated to an imperial prince body after a car accident that took his life. He found out that he is in a world similar to our own with a timeline akin to early twentieth century. The body that he is occupying was the imperial prince of a failing empire who suddenly rose to power after a successful assassination attempt of his father. Unaware that the attack is just the beginning of what is to come. He faces many challenges throughout. Will Thomas Harrier be able to live his second life in peace while running an empire and getting it back to its former glory? Or will he succumb into a conspiracy lurking within the country's borders?

Expect some:

Cold war era techs.

Super battleship with advanced electronics, propulsion, and fire control systems?
Helicopters?
Missiles?
Modern medicines and equipment?
AC-130?
A nuke?
Challenger or Abrams or Leopard?
F-4 Phantom or MIG-21?
Colored TV's.

Everything!!!

PS. Cover not mine, I just found it on google.

Ben, a postgraduate chemistry student, envisions a future where science unlocks the secrets of the universe. But fate has other plans. In a sudden twist, Ben dies and awakens in a strange new world, reborn as a five-year-old boy named Damian Sunblade.Damian's joy at being part of a noble family is short-lived. His family, valuing gold over blood, sells him off to another noble house to be groomed as a homemaker husband, a mere pawn in their political games. Struggling with his new reality and the remnants of his past life’s knowledge, Damian refuses to succumb to his fate.In his new household, Damian discovers that this world is governed by magic circles, Runic symbols wielding immense power. Driven by his scientific curiosity, Damian begins to experiment. Applying the laws of physics to the Rune symbols, he deciphers their secrets and invents his own unique form of magic.However, The family that bought him has their own plans for him, seeing Damian as a valuable tool to enhance their power. But Damian, ever the independent spirit, has dreams beyond servitude. He longs for freedom, a place to call his own—a life where he can use his talents without restraint.And so Damian devises a daring plan to escape. His journey is fraught with danger and intrigue, as he navigates a world filled with mystical creatures, powerful adversaries, and ancient secrets. Along the way, he forges alliances and battles enemies, all while refining his magical and scientific skills.In “The Runic Alchemist,” follow Damian Sunblade’s epic quest for independence and self-discovery. Witness his transformation from a forsaken child to a formidable Alchemist, determined to carve out an extraordinary future for himself in a world teeming with infinite possibilities.

Cosplayer Liu Mang accidentally crosses through time and arrived at the Eastern Han Dynasty wearing Aries Gold Cloth. (Saint Seiya!) He arrived on top of the walls of XiaPi right when it was about to fall to Cao Cao.

“Don’t kill me bro; I’m not working for boss Cao!”

“Hey! You’re slashing the wrong person! Boss Lu’s underlings are there! Not me!”

He accidentally saved Lu Bu who was tied up by Song Xian. He accidentally became the son in law of Lu Bu. He accidentally changed the history of the Three Kingdoms period.

When aluminum casted Gold Cloths are worn by generals like Zhang Liao and Gao Shun during the Eastern Han Dynasty, glistering on their bodies… When the soldiers in the camps are sporting mechanical crossbows… When crossbreeding of rice plants appeared on Lu Bu’s territory…

Liu Mang knows that a world belonging to Lu is coming.

- Description from Novelupdates

Lin Xun unintentionally downloads a text game called “Book of Salvation”.Leveling up and taking adventures is just standard procedure.Not only can he bring game items into reality, but he discovers that he can also bring game characters into the real world…Although the game difficulty is hellish, luckily, Lin Xun has an unusual talent.While other Apostles can only use one game character…Lin Xun is hesitating over which one of the game characters he should use.While other Apostles are still using weak human characters...Lin Xun is already using powerful monster BOSS characters.…Then one day, when Lin Xun brings a terrifying BOSS into the real world...“Would you believe me if I said I'm here to save the world?”