Immortal In The Magic World - Chapter 542 - Finishing off the Warlock Alliance

Due to a mistake on his student’s part, a super Martial Artist had received a wrong class in an online game and had become a mage. He who was used to curbing violence with violence and using strength to subdue strength could only make the best out of his mistake. Taking on a new lease in life, he became a violent close combat mage. When strength and magic came perfectly together, a new gaming path had been opened by him!

Follow Chen Ming as he accepts disciples, establishes a sect, and fights his way in a world that deems him a cannon fodder.
He goes against any common sense using his wits and novel knowhow to finish missions and arm himself against his cruel fate.

- Description from Novelupdates

Reborn as a sword, he lived for hundreds of years, and then he occupied the body of a 15-year-old prince.