I Became a Dark Fantasy Villain - Chapter 600

When her father passed away, her mother married into a large family. She thought it'll be a new beginning of her life, but it only brought her an substitute marriage to a disabled husband her step-sister didn't want.On the second day of their marriage, the noble and aloof man said indifferently, “Divorce or live as a widow, choose one.”She pulled off his suit pants and touched his firm and sexy thigh, “I choose the third option!”Latter, she used her medical skills to healing and saving people, including her disabled husband, who turned out to be a hidden billionaire!Nobles and celebrities sought medical advice, flocking to her like ducks.Those who humiliated her regretted it deeply, begging for mercy on their knees.The billionaire smiled proudly, “My wife is a treasure, only her husband knows it!”She rubbed her waist and gritted her teeth, “Didn't you say that you wanted a divorce and warned me to stay away from you?”

In a world teeming with Titans, Colossals, Gigantic Monsters and Kaiju's, Erian who reincarnated makes his living collecting scraps of low-grade Defective Genetic Serum, realised he transmigrated along with his system.

Follow Erian as he grows to become the strongest Disaster Grade Titan with the help of his Titan System!

“Here's what happened. I was in a desperate situation when I accidentally encountered a dragon. It told me I was a martial arts prodigy and said it would teach me the Dao of Immortality…” “This excuse for skipping class and cultivating in secret… is that seriously the reason?” “I don’t care whether it’s human or not, what matters is that the dragon said: ‘If you want to become strong, kneel and call me Master.’”

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.