Blackstone Code - Chapter 212:

A war veteran and an anime fan as well, he got into anime by watching it with his grandson after his retirement, his grandson loved pokemon and so did he also came to like this world of pokemon where people didn't kill each other and people used to have fun with there pokemon, after watching Pokemon with his grandson and playing with him all day he got back his childhood which he could never experience due to the cruel war, and as of now our MC has turned 82 years old he was very satisfied with his life with no regrets and waiting for death to take him away but will death be is end or will it start a new beginning, a new legend.

Who, in the ancient mythology, held an artifact and killed the first emperor of the human race?

Who, at the beginning of ancient times, closed the gate of the God Realm, Jedi Tiantong?

Who set a lifespan limit of only one hundred and thirty years for the people, and even the Great Emperor was not spared?

Who, turned into a black hand that covers the sky for eternity, shrouded the world?

…

Yang Shou on Earth: “Yes, yes, I did it all, I just want to live.”

- Description from novelbuddy

Lucius Lothra, a passionate gamer suddenly find not just himself but the whole world in a fantasy world where Knights and Mages exist.All Earthlings who once played a VR Game called System Online wake up in this world with their own Systems which they created when playing System Online. Lucius had just created an account when a world ending event occurred so he didn't play the game but he did manage to create his own system.The only problem that Lucius has is that he doesn't know if his system works or not and the only way to find out is... DEATH!!!

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.