Naruto: The Mist Within - Chapter 7 - : The Art of Seals

After 50 years of being in the position of Hwacheon Clan Leader, Kang-hyuk, widely renowned as 'The Dragon' retires.

After an unexpected accident, An Luo was reborn as the young master of a business family. Even as his grandfather’s favored grandson, he seems to only be a cannon fodder in the brothers’ struggle to seize power. However, the most frightening thing is… the strange emotions that flicker in his little brother’s eyes as he looks at him. At that moment, overwhelmed by his brother, An Luo angrily thought: Could it be that he is doomed to never escape this vicious cycle of “brotherly love”?

An Luo(frowning): After rebirth, I don’t want to be together with some strange person.

Someone(suddenly appearing in the back, smiling): What did older brother just say?

An Luo: …Nothing.

- Description from Novelupdates

Amidst a disaster, an orphan contracts a sickness.

In his waking hours, he is tormented by his ailment, but when he slumbers, there is infinite darkness.

One day, when he was five years old, a strange Fate Trickster appeared in his dreams. Ten years later, he dreams of becoming a lord. To do so, he takes a chance to trade his fate!

That day, Wang Zhong once again stood at the gates of the Tianjing Heroic Soul Academy. He was about to start a brand new life.

- Description from Novelupdates

Lu Zhiguang is not a cannon fodder himself, but his mission is to save the miserable cannon fodder.