MTL - Starting from Zero - v23 Chapter 60 They also have secret weapons!

A modern-day antihero, who was infamous for his devious acts, dies in an explosion meant to take down a powerful criminal syndicate. Waking up in a world of sword and sorcery, he finds himself possessing a fragile, powerless body with a strange “System” that seems broken. Initially thinking he's doomed, he learns that by pretending to be weak, he can manipulate others into revealing their secrets, granting him abilities they possess. As he rises in power, he discovers that the System was intentionally sabotaged—by none other than his own future self.

When an S-class elite assassin-raised captain of a special ops suicide squad comes home from a high-stakes Africa mission, he finds himself offered something that could potentially set him up for life- a curious assignment that he could use to finally exit his days of war and slaughter.

Then placed into a high-school setting, Lin Yi is tasked by the chairman of a top-tier multi-billion company with bodyguard duty for non-other than his own daughter, a certain little Miss of said high-school.

His enemies, once ranging from drug lords, mafia bosses, political figures, and national leaders, are soon replaced with spoiled kids who happen to have rich papas and mamas, and Lin Yi finds his intense expertise and high-threat skillset misused, and very underwhelmed…

But he does get a harem cast as diverse as his old enemies, so Lin Yi decides that, for the sake of messing around with girls as an invincible entity in a down-leveled environment, leaving his bloody and death-filled war days behind is something he’d definitely want to strive for.

- Description from Novelupdates

Sacrificing his life to protect his best friend was a decision which Hui Yue did not regret, yet who could have known that death was not the final destination, but rather the beginning of a new adventure into a world filled with demonic beasts and martial arts cultivation.

Hui Yue soon found that within this world, strength was what determined your future accomplishments and there was no space for the weak. Embarking upon this new life, Hui Yue meets friends, experience betrayal, and starts his own journey of cultivation to overcome his limits and become strong.

After killing the Demon King and returning to Earth, the world was in chaos due to the gates. Now, I just want to take care of my people and live as I please. After all, there’s no hero party here to oppress and bind me.