The Venerable Swordsman - Chapter 766 - Fight for Something!

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.

[Ding! Sorceress Beauty Merlin from Camelot has added you to a chat group full of beautiful maidens!][Ding! You've claimed the title of Supreme Demon Lord!][Ding! Fairy Queen Ophelia tagged you in a post!][Ding! Medusa sent you some of her spicy videos, shut your blinds before watching!][Ding! Your dog has been transformed into the Ancient Black Dragon Veligrpyh!]James Kang, once the youngest heir to the multi-trillion-dollar Hart Global Corporation, has everything anyone could dream of: money, luxury, and freedom. But his life is hollow—friends are fake, family distant, and his days are a blur of shallow extravagance.One late, lonely night, James gets a notification:[Congratulations! You have been added to the Ancient Multiverse Chatroom!]Thinking it's some cringy online role-playing game, he decides to entertain himself and plays along, proclaiming himself the “Supreme Demon Lord.”The group, filled with titles like:[Princess of the Azure Seas][Dragon Emperor of Ashvale][Goblin Slayer Supreme][High Priestess of the Sun][Fafnir, the Pet Wyvern]And they seemed hilariously invested in their roles.What starts as a joke takes a bizarre turn.The more James participates, the more he notices strange phenomena: glowing runes on his skin, magic artifacts materializing from nowhere, an elder dragon in his garage, and a sudden mastery of dark magic.Things escalate when a private group chat, run by a perverted female King Arthur, invites him to [The Table of Beauties], a circle of god-tier roleplayers… or so he thinks.Soon, James learns the truth.The chat is an interdimensional nexus connecting real worlds where magic, legends, and gods exist. His casual banter and fake roleplay have turned him into a living, breathing Demon Lord, complete with a castle in Hell, loyal monster armies, and reality-warping powers.To make matters even crazier, his “friends” start visiting Earth, and they’re nothing like he imagined!

It tells a poignant love story. He was the most heroic man in history, and before his death he sang a sad song about a woman; she was the most charming woman in history, and before her death she danced a story about steadfast love. The story of the two had no beginning, only an ending of parting in death. After his death, he became a demon for her, and fought fiercely with the immortals of the three realms. After he was killed, his unique seven souls were hidden in various places by the immortals; she became a ghost for him, and before she passed away, she smashed Meng Po's soup bowl, and her soul flew away. Even so, he still vowed to subvert the three realms, find her in the next reincarnation, and marry her, even if it took a thousand years.

With a square halberd in the palm, and a red rabbit and horse under him, nowhere can the world go!

- Description from novelbuddy