Country Maiden: Fields and Fortune - Chapter 28

Sometimes dying isn’t even the worst part of your dayMark has been reincarnated into a dead town in a bog, one that has been recently destroyed and occupied by ravenous undead. They disappear every day and return again at night, mindless and hungry, hunting for any survivors. He’ll need to use cunning and subterfuge to avoid them, because since he was transported into the body of a child, he can’t level up. At least not yet.Bog Standard. It means “totally normal”, right? But for the small towns found in these bogs, there's no quick rescue and not much trade. Everything has to be made to last. To them, it means “excellent quality”. Mark will have to prove he's Bog Standard if he hopes to survive.This is an Isekai of excellent quality. It’s a progression fantasy set in a LitRPG world, rags to riches with an eventual OP main character. The pacing is slow-burn, incremental progression, sometimes slice-of-life, punctuated by moments of intense violence and possibly traumatic content.

A good-for-nothing man married a beautiful girl but was kicked off the bed on the wedding night. Furiously, he wrote a bill of divorce and ran away.
He was schemed a car accident in which he nearly lost his life. However, it turned out to be a blessing. He swallowed the soul that passed through the outer world, thus obtained superb medical skills and martial arts.
Later on, with the silver needles and invincible martial arts, he embarked on the road of counterattacks and was committed to his great dreams.

- Description from Novelupdates

In the near future, a space channel connecting the other world suddenly appeared on Blue Star, and a large number of other world monsters poured into the homeland where human beings depended for survival.

Human civilization has shrunk sharply and had to hide in the base city to survive.

Only warriors can lead human beings to open up living space and regain lost land.

However, martial arts requires talent, and not everyone can become a martial artist.

People with outstanding martial arts talent can not only advance quickly and break through limits, but also optimize their exercises and benefit future generations, and are admired by all mankind.

By chance, Lu Heng discovered that his martial arts talent could continue to evolve…

- Description from novelbuddy

The Jiuzhou Continent contains an era of chaos and fiendish demons, haunted by mysterious beings and fraught with feuding martial families, demonic sacred grounds, and endless struggles between various powers. Conflict is a constant throughout the world.Within such darkness, Gu Chen opened his eyes to this reality.At the same time, he discovered that as long as he slew these fiendish demons and ghosts, his cultivation strength could continually elevate.Killing a Panic Level Demon yields a decade's worth of cultivation.Slaying a Ghost Level Fiendish Ghost brings thirty years of cultivation....Eventually, one day, staring at the endless swarm of fiendish demons and world-renowned grandmasters in his path, Gu Chen chuckled lightly, “Are you able to withstand this fist of mine, charged with 1600 years of cultivation?”