From Old Country Bumpkin to Master Swordsman

This is a wonderful Japanese light novel that gained popularity from viewers and their urge to be an anime, but it is a manga that is very interesting. 

This story is about a middle-aged man who turns into a sword saint. He achieved extra powers, and his personality is very humble. He uses his powers to fight intense battles. Sometimes you will enjoy comedy moments with action. It is full of interesting fantasy and exciting scenes.