Leon frowned when he heard those words. He didn't recall doing anything that would endanger Earth. If anything, he was working to avoid that humanity destroys itself… but then again, he never thought about the planet. Considering that mana could make almost everything and was a source of powerful energy, he concluded that his world was safe, but its inhabitants weren't.

"What are you talking about?" Leon frowned.

"Before that, tell me. When the monsters and dungeons appeared in your world?" Gurr asked.

"Are you seriously start this conversation answering a question with another question?" Leon frowned again. "… It happened almost five years ago."

"Five years… if one of the harvesters brought you here after such a short amount of time, then perhaps your world still has a chance…" Gurr said. "Listen… mana is a source of energy like no other. It can accelerate the production of food, make living beings stronger, and even prolong the life of those who have it. But there are several downsides to its use… the people of your world will soon learn that."

"What downsides?" Leon asked.

"It will be easier to understand if I tell the history of this planet…" Gurr said, grabbed a little of the lifeless earth near him, and let it fall.

That planet was called 'Miebos,' and in their language, the word meant 'grey'… they called it that because a great part of that world was covered in ice. Leon didn't have time to check, but it looked like the sun of that planet was quite distant from that world. That was why the temperature was low, and a long time ago, ice covered almost everything.

Eight percent of the Miebos surface was made of water. The remaining twenty percent was land… covered in snow. Then a group of people had an idea… the idea was to create their own sun. That happened two hundred years ago, and although at that time their technology wasn't that impressive, the inhabitants of that world managed to send to space a satellite that could collect vast amounts of solar energy. Then they used it to melt the snow of the planet. Although they could eat meat from the animals of their ocean, it looked like it wasn't easy to fish in that world, since several creatures inhabited that unknown part of the world. Regardless, their plan had been a success, after getting rid of the snow, they finally obtained the chance to cultivate their lands… and thus, the age of prosperity of Miebos began.

In one hundred and thirty years, the inhabitants of that world progressed so much that they even managed to sent a few astronauts to nearby plants and even created bases there. Science progressed to the point where parents could even decide the color of their children's eyes… but around the time the first flying cars got popular, the monsters and dungeons appeared.

"Out of nowhere?" Leon asked. "Didn't you guys notice anything weird that may have caused that?"

"At that time, no." Gurr closed his eyes. "But we noticed later why those creatures and mana appeared in our world. Those appeared at the very moment we begun to run out of natural resources."

Leon frowned when he heard that. Although some people have been discussed over the last decades that that kind of thing would soon happen on Earth, it didn't look like that had happened five years ago. Then again… Leon lived in a rich country, and his family was reasonably well-off. So, even if that kind of problem appeared in several parts of the world, it would take a while for him to notice that.

When the monsters appeared, Gurr was a member of the police force of the capital of the world. Surprisingly, even though the land was quite vast, there was only one country, and coincidentally, the destroyed city Leon saw before was the devastated capital. Although the place was several decades ahead in terms of technology in comparison to Earth, it didn't last more than a few days when dragons attacked.

"So, literally, the same events happened here," Leon said. "Dragons destroyed cities, and the small fries hunted the people of this world. Earthquakes made dungeons appeared, and even more, monsters came to the planet."

"Yes, the same thing happened here." Gurr nodded.

"Did the dragons disappear after a while?" Leon asked.

"Yes," Gurr answered.

"Do you know why?" Leon asked.

"No. Even the people above only have a few theories as to why they suddenly disappeared and then came back." Gurr explained. "It looks like at certain points in the history of every world. Monsters are bound to appear. Those monsters have the capacity to use mana, and thanks to it, that kind of energy becomes available to the people of the said world. And thus, a new age of evolution began…"

"Well, I can see that." Leon nodded. "Mana is a source of energy way too convenient, and if the society of a world can learn how to use it without worrying about extinction, the society of that world would evolve in many aspects… but why monsters appear? I can't see them as a natural phenomenon."

"We don't know that yet," Gurr said. "What we do know is the fact that dragons weren't supposed to appear alongside ordinary monsters. A sentient being would have to train for decades before one can obtain the power to kill them on their first stage. Their mana capacity was leagues above all other monsters… Besides, the fact that they appeared out of nowhere without using dungeons doesn't make any sense. Thus, we concluded that they were summoned by someone to accelerate the evolution process of the world and their inhabitants."

"Summoned? By who? The harvesters?" Leon frowned.

"No… even the harvesters don't have the power to summon dragons even in their initial stage," Gurr said. "They were summoned by someone far more dangerous and impatient… but we still don't know who."