MTL - I Have Nine God Tree Martial Spirits at the Beginning - Chapter 1 Jiang Shiran

The legendary Qin Chen from the Tianwu Continent accidentally fell into the Martial Domain because of his friend’s betrayal.

Three hundred years later, he was reincarnated on an illegitimate son of the royal palace who had been bullied.

He used his previous life accomplishments, concentrating on his skills, refining the pill, and rising against the sky, rising strongly, and embarking on a shocking journey that shocked the mainland.

- Description from MTL

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.

[Power System has beautiful Waifus as his spirits.]

[Read for the great plot and a perfect HAREM. There will be SMUT chapters only when required. The protagonist isn't Naive and treats his woman with care.]

[Read only if you want a great plot, sweet romance, a perfect harem, and good smut without any forced development.]

[Story would make sense as you progress I have avoided info dump and explained in a natural way to answer each question through the characters.]

*Ding!*

[Dual Cultivation System installed]

…

Yue Yan Gets kidnapped by the goddess on his sweet night with his girlfriend. She asks him to help her on a mission against the XieLong temple but he turns her down.

Later, some mysteries reveal their past and Yue Yan agrees to help her in order to meet his Bing'er again who has also been sent to the new world.

When he transmigrates into the body of Meng Long, he finds out he has a special Physique, the Supreme Yang body that stops his growth in Cultivation unless he Dual-Cultivates with a woman.

Yue Yan's new family had mistreated his predecessor Meng Long so he decides to leave the clan to embark on a new path with his beautiful concubine Xue Rou.

Join Yue Yan AKA Meng Long, in his Journey to reach the pinnacle of the world.

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!

—

*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