MTL - Ci Jinzhi - Chapter 53 make it clear

The hearse with the weird odor slowed to a stop before the entrance. The sound of pebbles could be heard bouncing on the ceiling. There were footsteps coming from the corridor, and there seemed to be someone sawing next door. The door knob to the room rattled slightly, and the faucet in the bathroom kept dripping even though it had been screwed shut. There was a rubber ball that rolled on its own underneath the bed. Wet footsteps started to surface one after another on the floor.
At 3 am, Chen Ge held a cleaver in his hand as he hid beside the room heater. The call he was trying to make was finally answered. “Landlord, is this what you meant by ‘the house can be a little crowded at night’‽”

- Description from Novelupdates

To survive, the unfortunate Gong Qiying, who became the lord of the Sein Dungeon, had to make his dungeon extremely “hellish”:Doors that “cannot be opened from this side”,treasure chests “triggering teleport traps”,a three hundred and sixty-five mile journey from the starting point to the BOSS room with no place to rest,monster knights with great bows on either side of a narrow bridge,and sinister ambushes around corners.There's also unavoidable visits to poisonous pits and hidden paths...Additionally, well-known fighters like Isshin Ashina, the Furnace Knight, Rajang, and the Scourge Legion bring unexpected surprises!Various unique rewards such as the Flaming Sword, Murky Hand Scythe, Rapid Slash Longsword, Sacred Oath, and Flame Empowerment will make you too happy to contain your joy!Gong Qiying: The most important thing in my dungeon is to ensure adventurers have fun!

However, he did not know that he was not raising just a harmless pet, but a biological weapon secretly made by the government… a real monster.

As a former librarian, Rand felt that he had been living an ordinary life, the one that he had reclaimed unconsciously every single day.

Recently, he has been a little upset because the pet fish he accidently brought home to raised seems to have undergo some strange changes

Well, it turned into a merman.

- Description from Novelupdates

translator: ShayanAuthor: flaming fortressIn a world where living beings are inslaved by godlike evil entities hiding in the shadows, monsters feeding on the flesh and souls of the living, worlds falling one after the other.how can the living survive and fight back?.......This is not a pure cultivation novel. This is a world where MC could die any second. He is just a small figure in the grand scheme of things, trying to survive where all hell has been let loose.