MTL - Armor Frenzy - Chapter 1845 best cover

I just left an honest review, and I was reincarnated. But not into the novel I criticized—into the world of [SSS-Class National Power Heir] .I reincarnated as Baek Seo-jun, the older brother of the original protagonist, faced discrimination, and was discarded as a sacrifice.And then I experienced hell.With the power of the final boss, I will exact revenge on everyone—whether it’s the original protagonist or the villains.[The protagonist who has gained the power of the final boss]

However, he did not know that he was not raising just a harmless pet, but a biological weapon secretly made by the government… a real monster.

As a former librarian, Rand felt that he had been living an ordinary life, the one that he had reclaimed unconsciously every single day.

Recently, he has been a little upset because the pet fish he accidently brought home to raised seems to have undergo some strange changes

Well, it turned into a merman.

- Description from Novelupdates

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.

Forget about moving to the other side of the world and starting over.The Apocalypse is here!As the only survivor of the Tutorial Quest in his area, Elijah awakens the Class of “Depraved Hero”, an ominous-sounding Class with a Legendary Rank!Additionally, because of the insane difficulty as well as his Clear Rank, he gains the Skills that, according to the mysterious figure that is the Administrator, he needs most.[You have Developed the Skill “Absolute Authority[A]”.][You have Developed the Skill “Slave Mark[C]”.]