Kinki no Tensei Daimadoushi

Dungeons appear without warning, and individuals with awakened abilities venture inside to seek treasure. Saeki, lacking any such skills, is seen as ineffective. To raise funds for his ailing younger sister’s treatment, he becomes an adventurer regardless. Unbeknownst to others, Saeki was once the world’s most powerful mage in a past life. After reincarnating, he must regain his strength through leveling up. The narrative follows his journey as he slowly rebuilds his power and begins to influence the world around him.