From Old Country Bumpkin to Master Swordsman (webtoon)New

Middle-aged Beryl Gardenant has only ever accomplished one thing: running a humble sword-fighting dojo in the quiet countryside. But when hes paid a visit by his former pupil, Allucia, he discovers that she has become an elite commanderand shes hardly the only ex-student whos a renowned warrior! Now forced by Allucia to become a special instructor to the strongest order of knights in the kingdom, can Beryl reach his full potential even though hes an old man?