MTL - Unlimited Cycles of Death - Chapter 9 The killing of Iris 09┃ was also an easy task.

Yuka, reborn as the daughter of the universe's richest man, tries to live a simple life. She gets a big shock when she has to join Union University of the Alliance because of government rules.In university, Yuka picks an easy major, hoping to keep a low profile. But her plan doesn't work. She keeps facing tough situations that show off her smart mind and strong skills. Yuka tries hard to live normally but keeps getting pulled into extraordinary accidents.This is the story about how Yuka grows. It's about her trying to hide her real identity while dealing with a world that always challenges her.

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.

In a world where power defines worth and survival is a privilege earned through strength, Ronan was just another broken soul—bullied, beaten, and forgotten.Until he snapped.[System Activated][You have acquired an S-Class Ability: Starflame][Extreme rage and deep-seated hatred detected][You have obtained the unique skill: Devil’s Covenant]Once a victim, Ronan begins to rise—with a system by his side that grants him power through every action.When he cooks:[Skill Acquired: Home Cook]When he reads:[Skill Acquired: Speed Reading]When he fights:[Skill Acquired: Vital Strike]And these skills?They evolve.[Skill Devil's Covenant has upgraded into Devil's Divine Judgement][Skill Speed Reading has upgraded into Hyper Comprehension][Skill Energy Slash has upgraded into Demonic Slash]Every moment, every breath, every choice brings him closer to power.A hero, or a villain?He stands among them.

Well-known Composer Fang Zhao was in the glorious stage of his career, when the Apocalypse arrived; After finally experiencing the bitter difficulties of a thousand dangers, when the Apocalypse was simmering down to an end, he collapsed; When he opened his eyes, he was reborn in a New World, 500 years after the end of the apocalypse, in the body of a student who had been dumped barely after graduation, who had been cheated of his hardwork barely after he started working…

The World of the Future, Virtual Idols PK Real Idols

“Every time background music plays in my head, I feel like there is nothing to be afraid of.” —Fang Zhao

Toward the end of the apocalyptic period, Fang Zhao lost his life. However, instead of dying, he found himself 500 years later in the body of a young and aspiring composer who shared the same name. Having received a second chance at life, Fang Zhao sets out to achieve the previous owner’s dreams.

Armed with the experience of living through an apocalyptic age and his profession as a composer before that period, Fang Zhao uses his talent, wits, and knowledge to make his mark in the entertainment industry of the future.

- Description from Novelupdates