The Earth After Rebirth - Chapter 56: So It Begins

Zhou Donghuang, a man from the Earth, is able to destroy any planet in the universe without lifting a finger. His supreme will can sweep across the vast cosmos in the blink of an eye. And his immortal spirit can depart from his body and wander around the universe!

In Kunlun Mountains lies a circular slate, which brought him back to one thousand years ago…

- Description from Novelupdates

…but it seems pretty doable.

An era where the desperate, miserable, and tragic tale of the six heroes who sealed the Dark Mage, who sought to destroy Maple World, became the favorite legend of children.

“The Cygnus Knights have fallen, the Resistance has collapsed, the Cross Hunters have been destroyed, and the adventurers have been annihilated. And the six heroes are dead.”

An era where no one dared to resist the reappearance of the Dark Mage and his followers.

“You are the only one left, El Paume. You’re the last adventurer.”

In that era, there was an adventurer who continued to fight until the end.

Humanity was on the brink of destruction. Muyoung, an assassin from the Forest of Death, fell to his knees. There were corpses all around him. For years, he had worked for the Forest of Death and had finally been able to eradicate them. Now, he, himself, was about to die. He closed his eyes as he felt his heart stop beating.