MTL - Start with Batman - Chapter 1 Start Dark Knight

Due to the increasing cases of suicide in the country, the government created a simulator system that was linked with human’s brainwaves, bringing them to transmigrate into thousands of worlds and experienced many aspect of life in order to stimulate the will of living. Only when the willmeter was filled 100% could they finally return back to life.Lu Yizhou. Male. Single. 22 years old. On a certain day, he committed suicide by burying himself in the land of snow. And then, he was pulled into the simulator.666: Welcome, host! Congratulations, you’re the 666th person who joined this project! Host is very lucky to get 666, because 666 is the handsomest, most sensible and most wonderful system!Lu Yizhou: …Can I change the system? You’re noisy.666: QAQLu Yizhou: No matter how many times I transmigrate, my willmeter will not be filled.666: N—No, don’t give up! Host shouldn’t give up QAQ uwaaa, don’t leave 666 alone! You’re my first, my one and only, how can you be so heartless and leave me behind like this?!Lu Yizhou: …why does it sound wrong?Thus, he started to jump from one world to another to save the villain.Lu Yizhou: Why do I have to save the villains?666: Ckckck, Host you’re too innocent! Of course, it’s because they are more awesome than the male lead; richer, powerful, resourceful, domineering and handsome!Lu Yizhou: …it’s only your preferences, is it?666: Host, why don’t you believe 666?! QAQHe thought that he had nothing left to live for. Bringing with him a weary heart and numb body, he sank to the bottom of the abyss only to find…a shining star.*******Beautiful, stoic, dense and unexpectedly naive gong x possessive, spoilt and scheming shou who knew how to use his charmAdditional tags: quick transmigration, fantasy, adventure, comedy, dark, mystery, tragedy, fast paced, seme/gong/top protagonist, love interest fall in love first, yaoi, mature, suicide thoughts, past play a big part, 1 vs 1

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.

Yukima Azuma—charismatic, confident, and utterly unforgettable. He was the man every girl wanted but could never truly keep. One by one, they fell for him, only to be left with memories they couldn’t erase.Kasumigaoka Utaha: “I was his first, the one who taught him love… only for him to use it on other women.”Sawamura Eriri: “If I hadn’t been such a tsundere, maybe things would have been different.”Yukinoshita Yukino: “He was my light in the darkness, the only one who ever truly saw me.”Yukinoshita Haruno: “That bastard ran away after taking everything from me.”Hoshino Ai: “My only true love. The one I can never replace.”And when asked about their relationship with him?“Ex-girlfriend.”But to the women still in his life?Sora Ginko, Kato Megumi, Sagiri, Bocchi, Shinomiya Kaguya, Kirisu Mafuyu, Suou Yuki, Alya—“Thieving cats.”Because no matter how much time passed, no matter how far he went—one truth remained: Yukima Azuma was the one man they could never forget.

Because of his master’s wine, he had somehow become the husband of a cold CEO — I’m still a virgin, please be gentle. He was from an ancient sect and had both Buddhism and Dao cultivation methods. The youth Qin Wu stepped out of the great mountain once again, stirring up the winds and clouds in the city.

- Description from Novelupdates