Behind me is the earth

You traveled to ancient times and found that supplies here were extremely scarce. Just when you thought you would be separated from your parents and family forever, alone and helpless, and thought the sky was about to fall, you discovered that you could travel back to the earth at any time.
Now you are full of ambition, reselling supplies, developing other worlds, buying a big house, raising little maids, making a lot of money, and living a contented life.
But you also find that this world is not as simple as a simple ancient background. Living corpses, martial arts, demons, ghosts, and supernatural powers have begun to appear.
This is the worst era, when people's livelihood is in decline and there are remains on the road; this is the best era, when warriors practice and supernatural powers are born.
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Ren Pingsheng: "Behind me is the powerful supply chain of the Earth's Industrial Internet in the 21st century."