Starting with Check-In Sacred Body of the Ancients - Chapter 136: Check-in at the Heavenly Dao Tower, the Thanos Saint King Gauntlet, About to Become One-Punch Man

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.

As a promise, he went out into the world as an assassin. 3 years later, after becoming the Supreme Assassin, he gave up on everything he had and returned to the ranks of ordinary people. But one day, Kismet, a mystical game created by the National Research and Development had appeared.

Enigmatic hands, spectral frame, and one cunning strike just like the swing of the Grim Reaper. The Supreme Assassin takes on the mystical world, and how his legendary tales sets off, progressively ascending the altar to becoming the best.

- Description from Novelupdates

The previous life is nothing but a joke. Being used completely then abandoned mercilessly. How can I be this stupid to not even notice such an obvious scam? Fortunately, I can have a second chance with my rebirth. Sister, Brother Yi and whoever mistreated me in my previous life, are you ready for my revenge and the counterattack of a princess?

An earthquake, another world, and a tentacle monster in his basement claiming to be his wife are just the beginning of a chaotic new life for Nick. He has new, dangerous, and exciting neighbors to get along with, people who want to kill him just for existing, and monsters with a taste for blood.But he's going to do his best to get to the bottom of everything and maybe even find a way back home. Even if he doesn't, he's at least not alone, for better or for worse.