I Possessed a Demon Sovereign - Chapter 36

Blue sky, white clouds, lazily lying on the beach, while feeling the gentle breeze coming from the sea. Hounds at the side with marine animals chasing each other around. Cups of unrivaled wine from his personal winery with cuts of prime A grade steaks readily around. For others, life is all about pursuing money, power, and fame, but for Jiang Hai, this type of lifestyle is what he constantly dreamed of.

- Description from Novelupdates

Gray was just a normal guy. No powers. No family. No future.In a world where strength and status decide everything, he was at the bottom.He worked hard just to survive, taking care of his little sister after their parents were gone.But no matter how hard he tried, life never gave him a break.And after losing his only job, Gray was ready to give up completely.Then something strange happened.Just as about he was to end his life, an unknown voice echoed in his ears.[Welcome to the Great Tycoon System.]And for the first time, Gray had a way to fight back.From being weak and broke, he’ll rise to the top—one coin and one job at a time.Because in the world where money can buy power, Gray is about to become the richest and strongest man alive.

Being able to see into people's past has no real appeal for the teenager this story is about, letting him use it only as amusement and to show off when he was drunk.Never watch into someone's past beyond a superficial level.Never try to find out more than you should.NEVER. EVER. LOOK. INTO. THE. FUTURE.But everything changed the moment he was forced to look into the future, was forced to investigate a murder, and was forced to make the acquaintance of the victim's twin brother('s fists).The more time passed, the more it appeared that the primary reason for this murder wasn't a local problem, but a global one.This single, marred corpse was the beginning of a threat that would shake the world.(MC looses a screw when he enters the prison)BL, first-person view; MC is shuo (perhaps even a reversible couple); love interest falls in love first; both MC and ML are straight, mutual bending, Enemies to Lovers

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.