Shikkaku Mon no Saikyou Kenja
失格紋の最強賢者 ; 失格紋の最強賢者 ～世界最強の賢者が更に強くなるために転生しました～ ; Shikkaku Mon no Saikyou Kenja - Sekai Saikyou no Kenja ga Sara ni Tsuyokunaru Tame ni Tensei Shimashita ; The Strongest Sage of Disqualified Crest ; The Strongest Sage of Disqualified Crest~ The World's Strongest Sage Reincarnated Himself to Become Even Stronger~
Shikkaku Mon no Saikyou Kenja manga summary: In a certain world, there was someone who excelled in magic combat, people called him 『Sage』. Seeking the strongest combat art, he devoted himself to research every magic and combat arts in existence. And the conclusion he arrived at was very cruel, 『My body is not fit for magic combat』. Yet he didn’t give up. He sealed his own soul with a magic art, and was reborn in a far-off future. And the magic theory in the completely changed world he saw there was of unbelievably low level.