From Overshadowed to Overpowered: Second Reincarnation of a Talentless Sage

Ephtal is a talentless boy who dies twice. The first time, he is reincarnated in an alternate world where he devotes his entire life to studying magic, only to discover he has no talent for it and die of anguish. He is subsequently reincarnated again, 400 years after his "first death." Having retained his memory and his power, he resolves once again to aspire to the pinnacle of magic.