The Runesmith - Chapter 408: Passing Through.

This story is centered around the man named Yi Ji-Hyuk, who has spent 1000 years in a Medieval Western fantasy-like world before returning back to the modern-day Earth. When he returns, he finds that his home is facing monster threats, and that humans with superpowers have appeared to protect the innocent people of Earth.

This novel is also known as Gu Daoist Master

Humans are clever in tens of thousands of ways, Gu are the true refined essences of Heaven and Earth.

The Three Temples are unrighteous, the demon is reborn.

Former days are but an old dream, an identical name is made anew.

A story of a time traveler who keeps on being reborn.

A unique world that grows, cultivates, and uses Gu.

The Spring and Autumn Cicada, the Venomous Moonlight Gu, the Wine Insect, All-Encompassing Golden Light Insect, Slender Black Hair Gu, Gu of Hope…

And a great demon of the world that does exactly as his heart pleases!

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*Gu (蛊) referred to poisonous insects in various cultures in South China while in folklore Gu spirits could transform into all kinds of species.

- Description from Novelupdates

Lynch crosses over to the Wizard World and becomes a Wizard Apprentice specializing in Biological Transformation, armed with a Skill Level system.Thus...He equips a lizard with bat wings, transforming it into a ferocious yet adorable Dragon Attribute creature.He transplants gastric mucosa to the Cannibal Flower to enhance its digestive system.He equips the Poisonous Mushroom with a mouthpiece, transforming it into a Little Spraying Mushroom.Transplanting eyeballs, modifying organs, adding limbs...From a little wizard, he hustles his way to becoming the master of the world, starting from the transformation of low-level Magic Plants until he creates an Angel.

Chen Feng, of modern earth, had suffered bad luck since birth. After finding the legendary “lucky artifact,” his bad luck peaked and he became the only person killed in an earthquake. By a twist of fate, he found himself transmigrated into a different and magical world! A world much larger than earth. A world only partially explored due to the dangers within. A world where human civilization centered around genes. In this world, human beings possessed all sorts of abilities due to genetic fusion. Some went on to create world-changing technologies with their mysterious genetic abilities, while others went on to become undefeated genetic warriors with their combat genetic abilities. How will Chen Feng fare in this new world?