100-nin no Eiyuu o Sodateta Saikyou Yogensha wa, Boukensha ni Natte mo Sekaijuu no Deshi kara Shitawarete Masu

After raising 100 saints and ending the conflict with a malevolent god, Eisen saves the world but suffers a terrible injury. He leaves for another world to recover. The heroes he trained use their abilities to help that world flourish. Longing to see their revered master again, they send him detailed letters about what they have achieved. As Eisen reads their accounts, he decides to travel around the country and visit each of his former pupils.