The Zashiki Warashi of Intellectual Village - Volume 9, Chapter 2: Colorless Prequel@Uchimaku Hayabusa

Bought it right away.

The genius pharmacist transmigrated into a pitiful farm girl’s body. Ignored by her own father, abused by her stepmother, and bullied by her stepbrothers. Her “twin” brother was given to distant relative and she went as the “extra” to live under someone else’s roof.

Luckily she possessed mad apothecary skills. Collecting herbs, plowing herb fields, formulating medicines and treating the ills, she refused to live an ordinary life as she slowly uncovered the truth of her real identify.

Inadvertently, she saved a dashing man who was in reality a big, bad wolf hiding under the skin of an innocent little puppy. He pulled out all his tricks: I have no other means to return your favor of saving my life. What say I repay you by marrying you?

- Description from Novelupdates

Lin Wudao has traversed, and there is an invincible corpse collection system.

As long as you collect the corpses for the strong, you can get the things they owned or touched as rewards during their lifetime, and the obtained items are still strengthened.

Lowest, ten times stronger!

[You collected the corpse of the great emperor Jiang Taichu, and gained ten thousand years of cultivation! 】

[You collected the body of your fiancée Jiang Qingxue, obtained the Zichen Sword, a humane spirit weapon, and after strengthening it ten times, it was upgraded to become an extreme spirit weapon, the Xuantian Ancient Sword! 】

[You collected the bones of an immortal, obtained a ray of immortal origin, enhanced it by 100,000 times, and upgraded it to become the original origin of Hongmeng. After refining it, you can be promoted to the immortal emperor! 】

…

Since obtaining the invincible corpse collection system, Lin Wudao has embarked on an invincible road that can push through the ages and suppress the heavens.

- Description from novelbuddy

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.