Longevity: Starting from the Qi Tags - Chapter 1171 - 511: Invincible Under the Heavens!

This is a story of a man named Kim Sae-Jin, who one day, inexplicably wakes up as a Monster. Follow him and his perilous journey to get his life back as a Human, all the while growing even more versatile as a Monster in the process. This should be… complicated, somewhat.

A martial art expert from the Song dynasty lives like a Phoenix that can live again in another body after death. This time, he happened to take over the body of a Japanese high schooler who is also a victim of bullying and has a bit complicated family circumstances.

The King of Hell sentences you to death by midnight, but I can ensure that you live past morning.

The young man, Qin Lang, received the inheritance of a poison school by chance. He uses poison to kill people, uses poison to save people and he uses poison to chase beauties. With body of ancient extinct poison and a body of a martial artist, he walks around the city, and wanders around in the underworld.

- Description from Novelupdates

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.