That Inferior Knight, Lv. 999

A brief description of the manga That Inferior Knight, Lv. 999: 

Yuan suffers from misunderstandings, anger from family, enemies and mentors. Yuan is considered a weak student who has mastered the art of magic and military technology. This causes constant misunderstandings. Yuan is an ordinary boy with a good soul who gets upset every time he thinks about his lack of talent. His family is a wise master of martial arts.

In fact, the boy is the strongest in the world. Because Yuan is weak, he was kicked out of the house to find his way. At the age of eight, he defeats the army of angels. He thinks dragons are ordinary lizards. The boy thinks he must become even stronger to be a noble hero knight. One day he’ll be free from his delusions.