MTL - Little Mermaid Dressed As a Scientist - Chapter 39

Before death Qin Tailong left two magic tools to his son, Qin Dong. In his father’s last words, Qin Dong realized his father had been murdered by Lord Wanpeng, who coveted one of the family magic tools—mystic chaos ring. Bearing the hatred in mind, Qin Dong swore to revenge against his foe. He escaped to the mortal realm temporarily, continued to strengthen his cultivation base and studied the secret hidden in the seals of the ring. While reveling the secret, he found five ladies were the key to the release the seals. Their romantic relationship with Qin Dong was established the moment he was born.

- Description from Novelupdates

The one single goal in life of the Strongest Old Sage is to subjugate the Demon King. In an epic final battle, both of them met their mutual destruction at each other’s hands.

However, the Demon King was not completely destroyed!

In order to destroy the Demon King once and for all; post-death, the Old Sage trains in the World of Gods and reincarnates as the Apostle of the Gods, Will.

In the reincarnated future, the Old Sage had become a legend and his former disciples hold the supreme authority in the world. The disciples had created an organization to oppose the Demon King and an academy to nurture the new generation of Heroes.

Thus the Apostle of the Gods, Will (8 year old), enrols into that Academy of Heroes.

This is the story of a boy on a mission to save the world through epic battles while enjoying Academy life.

Revenge is the only thing she wants after knowing the truth.

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.