Black Clover: The Son of Fire Dragon Igneel - Chapter 327: SFDI -

A boy from 21st century Earth, met an accident and later was reborn in Naruto’s Ninja World.
He is born in Uchiha Family and becomes the useless brother of Itachi Uchiha and Sasuke Uchiha…. Let’s see how he changed the Naruto world.

- Description from Novelupdates

The plague of insects descended overnight. As an ordinary person without invincible powers and extraordinary exercises, facing blood and death, what should we do at the critical moment of life and death?

(I am a reasonable party, but the novel needs appropriate YY, please do not excessively investigate the rationality of the background in a razor-sharp way.)

- Description from novelbuddy

Song Cheng transmigrated and became a blind errand boy in a medicine shop in a remote town.Fortunately, after he found a wife who did not disdain him, his “Golden Finger” also followed.Demons and ghosts roamed the Chaotic World, Profound Techniques went with Occult Sciences, Divine Weapons dazzled the cosmos, the Yin and Yang were inexhaustible.Song Cheng did not seek to dominate as a king, he simply wished to live his life well....This is the story of a person with Longevity, who walked through long years and witnessed innumerable Dynasties.

He had crossed into the dark, ruthless Wizard World.Lucien found his system somewhat different from the usual golden finger.System upgrade points? Chip activation?None of these, but rather becoming a role model, transforming into a nurturing breeze:Teaching students knowledge, receiving advanced knowledge in return.Caring for and maintaining students, earning generous rewards.[Your student has mastered the Magic Potion “Kuru's Cough,” congratulations on acquiring the improved formula “Kuru's Cough - Enhanced”!][Your student has mastered witchcraft “Fireball,” congratulations on learning witchcraft “Greater Fireball”!][Your student has successfully crafted the wizard's tool “Pale Mask,” congratulations on acquiring the wizard tool’s manual “Revised Pale Mask”!]Initially, Lucien was resistant.But after experiencing what it was like to teach disciples and outdo them, Lucien felt he had completely transformed into the form of the master system.This thing, isn't it much more useful than something called Cheating Device?