MTL - Comprehensive Manga: The Wandering Ninja World Started From Questioning Payne - Chapter 16 Question 4

After mistakenly contributing all of his attribute points to the drop rate, Xiao Shi found that every time he killed, he would get an item.

Slapping a mosquito to death, drop a pill.

Killing an evil spirit, drop a secret book.

Slashing a martial artist to death, drop the opponent’s cultivation tips.

….

When killing, Xiao Shi was shocked… “How did I become invincible?”

In the waves of steam and machinery, who could achieve extraordinary? In the fogs of history and darkness, who was whispering? I woke up from the realm of mysteries and opened my eyes to the world.

Firearms, cannons, battleships, airships, and difference machines. Potions, divination, curses, hanged-man, and sealed artifacts… The lights shone brightly, yet the secrets of the world were never far away. This was a legend of the “Fool”.

- Description from novelupdates

Fear breaks the boundaries between dreams and reality, and it is impossible to tell which is reality and which is illusory. When the nightmare really comes, no one can be alone.

This is both a danger and an opportunity.

- Description from novelbuddy

10 years ago, after “the Gate” that connected the real world with the monster world opened, some of the ordinary, everyday people received the power to hunt monsters within the Gate. They are known as “Hunters”. However, not all Hunters are powerful. My name is Sung Jin-Woo, an E-rank Hunter. I’m someone who has to risk his life in the lowliest of dungeons, the “World’s Weakest”. Having no skills whatsoever to display, I barely earned the required money by fighting in low-leveled dungeons… at least until I found a hidden dungeon with the hardest difficulty within the D-rank dungeons! In the end, as I was accepting death, I suddenly received a strange power, a quest log that only I could see, a secret to leveling up that only I know about! If I trained in accordance with my quests and hunted monsters, my level would rise. Changing from the weakest Hunter to the strongest S-rank Hunter!