Kenja no Mago

A young man who died in an accident is reborn in another world as an infant. He is found by the patriot hero Merlin Wolford, who names him Shin and raises him as a grandson. Under Merlin's guidance, he learns various teachings and gains remarkable abilities. However, when Shin turns fifteen, Merlin admits he neglected to teach him basic common sense. Shin's unusual journey in this new world begins.