Rise of the Devourer - Chapter 12Book 3: — Spear Training

On the surface, he was striking and dashing, an object of envy and resentment from all men, but in secrecy, he was the formidable figure that made powerful leaders tremble. A marriage contract had brought him back to the city,In the bustling metropolis, a man fierce and enigmatic like a tiger, watch as he forged his own legend!

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

[You have transmigrated, named Gu Sheng, and are a farm boy.][This is a dynasty in chaos, where demons and monsters lurk and bandits run rampant; as someone at the bottom, you face hellish survival difficulties.][You decide to lay low.][You awaken a mastery panel.][You breathe a sigh of relief, you can start grinding.][You grind Chopping Wood to Perfect, chopping bones and breaking tendons with ease.][You grind archery to Perfect, becoming a godlike archer who can hit a louse at a hundred paces.][You learn the Iron Stone Fist, set foot on the path of a Martial Artist, and grind it to Perfect, with punches as heavy as a million pounds.]……[You learn the Longevity Eternal Youth True Art, greatly extending your lifespan, giving you more time to grind, and greater hope to lay low.]……[You grind to the limit, steadily laying low, and one day you suddenly realize, you are invincible.]