Anime: I Want Harem - Chapter 13

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.

Manchester United, once a dominant force in world football, finds itself struggling under Erik ten Hag despite having the financial power to rebuild.Big-money transfers fail to restore the club’s glory, forcing Ten Hag to shift his focus to homegrown talent.Among the overlooked prospects in the U18 squad is Leo Calderon, a 17-year-old central midfielder buried deep in the pecking order.Lacking physicality and dismissed by teammates as weak, Leo endures constant ridicule from those who dominate with strength and athleticism.But during one ordinary training session, everything changes—Leo suddenly sees passing lanes no one else can, angles of play invisible to even the most talented prospects.Yet, there’s a problem. His vision surpasses his ability. The passes he attempts don’t connect, his technique unable to match his newfound awareness.Coaches dismiss his efforts as sloppy, and his struggles continue. But one unexpected observer—a visiting League One assistant coach—notices something different.He watches Leo’s movements, seeing potential where others see failure.As Leo fights to prove himself in an unforgiving system, the question lingers—can he refine his raw talent before the club moves on without him?

I just shut the door, why should I kill the devil.

No, I need a demon hunter, Dante, it’s up to you.

Cultists, demons, traitors, and even fanatics, it seems that there are too many things to cut. This world needs justice, and now justice is angry.

(Mainly the PF system, and then the Pathfinder Wrath of Righteous mod. Note that mods are not games.)

(In the end, all the dice in this novel use real dice, not dice girls, nor set by myself.)

- Description from novelbuddy

Genius, antisocial, solitary, intractable , maniacal.

At the turn of every era, it is he who raises the flag of the rebel cross.

Winners take it all, losers take the fall.

He who brings order to a chaotic world, assembles talents and masterminds.

He who hides among the crowd, yet stands on the top of the world.

— The one and only, him.

- Description from Novelupdates