I Regressed to My Ruined Family

" I was born as the oldest of a renowned swordsman family, and became stronger faster than anyone.\nYet, I could not stop the dragons, a great disaster that had appeared on the continent.\nI closed my eyes in my final moments, thinking everything was over.\nI really thought it was over...\nBut when I opened my eyes, I was back in the past.\nA past that was very different from the world I knew.\"What? Is this really my body? Why don't I have any mana?\"\n\"Where did the castle go? Why's there only a wooden house left?\"\n\"...What? The dragons and humans made a non-aggression pact?\"A family that had fallen and was on the brink of ruin.\nA family whose writing of divination had vanished.\nAnd a body in which no mana could be found!\"...I'll have to keep myself busy from now on.\"The great hero of a renowned swordsman family.\nHe is back in the past, in a 'parallel world'. "