MTL - Adopting and Raising the Male Lead and the Villain - Chapter 4 Cousin

Perhaps it is the choice of fate. As a senior otaku, Qian Lingfeng got the “steel shell system”. However, when he swept the world with the system, became a local rich man, made all kinds of beautiful women, opened a harem, and realized the ultimate fantasy of thousands of otaku, he found that things seemed far from simple!
When the end comes, biochemical zombies suddenly come down, fierce beasts are in power, bloodthirsty zerg roam to kill the world, and human lives are comparable to dirt. Where will weak human beings go in this world? Is humanity going to be extinct? Or … can an otaku save the fate of the human race?

- Description from Novelupdates

What is it like to be a prison guard in another world? Thieves, pirates, assassins, con artists, terrorists… Werewolves, vampires, witches, necromancers, succubi…This is the Iron Rose Prison, where the most dangerous witches in the world are gathered.“I will make this the best model prison in the world!”said a prison guard who had been transported to another world.“Warden, someone has escaped again!”“Bring them back and put them in solitary confinement.”Today, is also a peaceful day on the Rose Prison.Warden: “I’m just trying to run my prison properly, how did I become a big shot in this world?”

Ye Fan accidentally obtained a billion crystal technology system, and since then, he has become out of control.

Android: You do n’t even have a mobile phone system. I want to make it impossible for you all!
Ye Fan: Sorry, I researched it out, it seems to be more powerful than yours!
BMW Benz: Our engines are famous all over the world!
Ye Fan: Sorry, I do n’t have an engine, I only have magnetic levitation, and the speed is only a few times that of yours. Do n’t worry, take your time!
…
Enemy: Is he still human?
Who can stop this!

- Description from Qidian

The world’s top level hacker, Shi Lei; due to him hacking the world’s top military powers during a joint exercise and attempting to steal information from them, ultimately leads him to get sold out by his own organization. This act eventually caused his own death by a missile bombardment.

God was playing a joke on him and allowed him to return back to six years ago, the autumn season of when he was still at his university. Being given another chance, plus the fact that he retained his ability as one of the best in hacking technology, Shi Lei decided to change his life! During his previous life, he was only an assassin in the dark. Although such an existence made people afraid of him, he would have to always hide within the shadows. In his new life, not only does he want to be an assassin in the dark, he also wants to stand openly in the middle of the world stage. Creating a world-class super enterprise, he will single handy change the whole world!

- Description from Novelupdates