MTL - Travel to a Primitive World to Build Infrastructure - Chapter 90

Xia Zhijun got the title ‘study god’ after scoring first place in the whole city. He’s the model of a good student in a teacher’s eyes: good grades, good manners, and quiet. When he wasn’t smiling, his entire body emits a cold abstinence aura. The girls only have the guts to look from afar and not get close.
Later, it was rumored throughout the entire school that even the study god would fight and hit on girls. Whoever dared to provoke his girl, he would teach you how to be a person at every minute. The night of the graduation ceremony someone saw him blocking Gu Siyi in the corner. He didn’t stop kissing even when she cried. He bit her lips and said in a raspy voice, “I’m going crazy…”
During college finals, Gu Siyi almost bursted out crying, “I’m such a failure. I won’t be able to find a good job in the future…And if I can’t find a good job, I can’t provide for myself…”
Xia Zhijun played with her pink earlobe and remarked, “I’ll take care of you.”
After they graduated, Xia Zhijun created a research company and Gu Siyi became the boss’s wife.
The commercial rocket, “Star of Siyi” was successfully launched. So everyone knew that the new technology superstar, Xia Zhijun has a wife who he spoils a lot.

- Description from Novelupdates

An Imperial Scholar by day. An assassin by night.The World of Cultivation has changed.Elemental Mancers. Flux Mancers. Spirit Mancers. Soul Mancers.Raining down fire and splitting oceans. Destroying mountains with a single stomp and calming skies with a glance. Controlling the tides of Karma, while wielding the souls of others like a puppeteer tugging on the Lines of Fate.The most mysterious of them all were Spirit Mancers, a truth that Theron was more than intimately familiar with. Due to one's Tribulation, his life was turned upside down. His family, his rage, his somber sadness becoming nothing more than Bad Karma's fuel for a madman.He was once a gentle young man, a non-combative Water Mancer who wanted nothing more than to read his novels to the sound of the rain and one day become an Imperial Scholar.But now...Everything had changed.He donned a cloak in the silent night as the clouds above gathered. Pulling its hood over his chilling blue eyes, he stalked off into the darkness.The first droplets fell.He would become the nightmare of his enemies, the blade hidden in the shadows of Heaven's tears.The River of the Night.

Lucius Mc. Conol, once the leader of a ghost division, is captured and killed on a mission. However, not all is lost as he finds himself reincarnated in another world... as a leafling?

Join Lucius as he teaches lower leveled plant life human tactics, bringing to them new concepts and powers.

*Ding* [You've leveled up]

This is a kingdom-building, evolution story which sees Lucius encounter beings from different species, spreading his influence and 'mystical' powers.