The Academy’s Time Stop Player - Chapter 122

An orphaned boy with dreams of making it big through being a blacksmith is given a once in a lifetime chance to succeed when he's taken in by an odd pair - Eggor and Ella. While former teaches him the arts of craft, the latter teaches him the mysticism of cultivation, granting him two paths to tread in this life.

He became a teacher at the best magic academy in the empire.
….For being mistaken for someone else.

My whole life, all I wanted was power.

I churned the world into rivers of blood and eventually gained the title, “Demon Lord of Strength”. However, all this became useless when I lost to a party of heroes.

But what can a loser say? As I laid dying, I was forced to listen to the hero’s gibberish:

“If you are born again, I hope that you will live a kind life!”

But huh? When I opened my eyes again, I was back in the past.

“What do I have to do to live a kind life?”

This is the beginning of an ex-Demon Lord’s journey to live a kind

Bai Yu traveled to the world of One Piece and activated the strongest swordsman system at the beginning.

No need to practice, swinging a knife will become stronger!

Thus, Bai Yu started his daily routine of wielding a knife.

Swing the knife 1000 times, and get the limit of physical strength – six styles.

Swing the knife 2,000 times to obtain the powerful Qinglong Sword Intent.

Swing the knife 3000 times, get three-color domineering.

General Huang Yuan: Bai Yu is the strongest rookie I have ever seen.

General Aokiji: My freezing ability was directly chopped into pieces by Bai Yu!

General Red Dog: Dangerous! My marshal position is about to change!

Hawkeye: Bai Yu is the number one swordsman in the world!

Since then, the name of Bai Yu has resounded throughout the world of pirates.

- Description from novelbuddy