MTL - History’s Strongest Senior Brother - ~ 1809. Three pieces

Zero, a 35-year-old mercenary, after being betrayed by one of his teammates who told his enemy about him. He chooses suicide so that he can kill his enemy and his traitor teammate. After that, he was reincarnated into the world of magic, in the body of an 18-year-old teenager with the same name as him. However, his body does not have mana or the talent for magic. But with the help of the cultivation system, he has unrivaled power in the world and has a harem of beautiful wives.

Civilization is destroyed and records lost. Only Dudian survives in a cryogenic sleep. Three hundred years later, Dudian wakes up and must become Dean to survive. Who can he trust in this world overrun by monsters without and within?

- Description from Novelupdates

5 years after the world changed, the final boss appeared.

He called himself a human. However, the world revered him as a god. The epic adventures of Yeon Woo-jin, who possesses extraordinary psychic powers, unfold in a ruthless world.