MTL - Traveling To The Last Days To Protect You - Chapter 159 Extra Eighth

A teenager named Evan Mason was reincarnated into the magical world of Harry Potter and goes to school at Hogwarts!
With only his knowledge of the future and great talent for magic, he takes the path towards the top of the magic world, only to realize that ever step he took, changed everything!

- Description from Novelupdates

This thought had grown deep in William’s mind!

Athar VonCruz, an orphan, had always been at the bottom rung of the society. He had been bullied, belittled and pushed down for his entire life.Beast taming in this world is not a hobby or a profession but is the only way of survival for a human and to gain power.Athar invests his entire life savings for one of the beast eggs; the only chance he has to rise and get ahead in his life.The egg cracks, and a creature of unknown potential emerges from it. In that pivotal moment, Athar's destiny irrevocably shifted. In that moment, Athar unearths a strange and wondrous secret; a hidden power that would become his ultimate trump card.Read how Athar VonCruz carves out a path out for himself and strives to reach the pinnacle of life.

The world was once at war with 10 alternate worlds. This was known as the Concept War and our world won 60 years ago. All of this was concealed so no normal people are aware of this fact in the current time.

After the death of his grandfather, the high-school student Sayama Mikoto is suddenly summoned by the giant corporation IAI. He learns this world is headed for destruction due to the acceleration of the Minus Concepts. To prevent this, negotiations must be undertaken with the survivors of the other parallel worlds so their 10 concepts can be released.

And so Sayama is caught up in the final battle to clean up after the Concept War which left behind so much enmity.