Lord Shadow - Chapter 1838: Two Suns

A broken man who ended his own life finds himself reincarnated into the game he used to play. However, instead of becoming the protagonist or a powerful antagonist, fate places him in the role of a minor villain—a mere stepping stone for the protagonist in the game's first arc.

Kanda Kyoichi transmigrated to Konoha and became a temporary instructor at the Ninja Academy. Fortunately, he awakened the Mentor System.By teaching others, he could earn rewards.Thus began Kyoichi’s career as a “teacher” in the ninja world.Shisui: “Sensei’s unique interpretation of the Will of Fire has given the Uchiha Clan a true sense of direction!”Asuma: “The essence of the jade lies in protecting the people, with the advanced leading the way for the less experienced. Only then can Konoha become stronger!”Kakashi: “He’s my life mentor. He transformed Konoha!”...Years later, in the memoirs of Kyoichi, now the Hokage, he wrote:“I honestly just wanted to be a life mentor!”

An unexpected journey took a group of university students into a secret room from which, upon returning, they began to disappear one by one. In order to unravel the mystery, they joined forces, traversing heaven and earth, diving deep into seas, crossing the farthest corners of the world, and even daring to time travel, only to find that behind each puzzle lay yet another.

Su Yun was a prodigy, blessed by the gods. However, life is never so easy. Soon after reaching 6th stage in spirit novice realm cultivation, his progress stagnated due to incurring a rare medical condition.

A few years go by, and Su Yun has spent all his time gambling or drinking, wasting his youth away, but one day everything changes. Qing Er, the only one who stood by him was forced by his clan to be a sacrificial bride to someone she didn’t love, only to be executed by the groom on the wedding night for fleeing. Burning for revenge, he scoured the world for a cure for his rare medical condition from both righteous and villainous side.

Countless years go by, and finally Su Yun not only found a way to cure his rare condition but also gain immense knowledge on a myriad of martial techniques.

But before he could fully cure himself, he received news that the groom suffered an assault that damaged his internal organs. Rather than wait for decades to become fully cured, Su Yun decided to hatch a plan for the assassinate of the groom. Unfortunately, he underestimated the strength of the groom’s family and was killed instead.

Then he regains consciousness. He comes to a realization that he went 15 years in the past. This time, he vowed to protect Qing Er, but first he must cure his rare medical condition. Will he learn from the mistakes of his previous life or is everything still set in stone?

- Description from Novelupdates