Kokuma Musou - Ochita Seikishi to Fukushuu no Kuro Madoushi

Synopsis

A sorcerer of black magic rises from the depths of hell to take revenge on the hero who betrayed him and his comrades in arms. However, the sorcerer could not defeat the hero and turned into a poisonous mist that poisoned the World Tree shrine. But a holy girl manages to resurrect him, will the sorcerer be able to avenge him?!!!