MTL - I Have a Treasure Trove - Chapter 529 A surge of two billion!

Lingyun, a fierce and savage cultivation genius takes over a dead teenager’s body. Coincidentally, they are both named Lingyun. Set in a alternate version of the 21st century, teenager Lingyun has been killed by someone with a grudge.

The world that nurtured the civilization which reached the pinnacle of magic was on the verge of destruction.
The last survivor transmigrated to the past, when the magic civilization started growing, as countless mages were still fumbling their ways through the thorny paths of magic knowledge.
He, who came from the end of the magic era, aim to reach the pinnacle of magic.

Cao Xin, a young man on earth, died in a car accident, traveled to a troubled world where supplies were scarce, and obtained a “Bronze Immortal Gate”…

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- Description from novelbuddy

Shen Yuan, a normal human who was living his life peacefully on earth died mysteriously, only to get reincarnated into the world of cultivation with an unknown bloodline so powerful that it even surpassed his chest system....“Hmm, looks like becoming an alchemist might be good. System, purchase the Alchemy knowledge.”[Ding!][Congratulations Host, for acquiring Heaven Refining Alchemy Sutra.]...Follow to see the journey of how Shen Yuan creates the strongest harem since the Primordial times to journey the three thousand world.