Fukushuu no Tensei Kizoku: Subete wo Ubawareta Dai Kenja, Onore wo [Fukusei] Shite Nidome no Sei wo Eru

Bring back the cruelty of the corrupt, power-hungry nobles! A classic dark fantasy begins! In a world where it's common for nobles to oppress captives, Rain is a genius magician who was born a captive and earned the title of "Great Sage." However, his magic, the status and honor he gained, only made him an eyesore and a target for elimination to the nobles. After being trapped and brutally killed, Rain uses his own magic to duplicate his own soul. Reincarnated as the heir to his sworn enemy, he vows revenge on the nobles who killed him! Now it's time for the purge.

(Source: Shueisha, translated)