Isekai Cheat Magician

The tragedy of the "Bloody Rhapsody" - the worst battle in the history of the world - is about to befall the world once more. With dark magic turning the soldiers into berserkers who can't distinguish friend from foe, both armies begin advancing on the royal capital to slaughter it and everything that lies beyond. Faced with countless berserkers, Taichi is forced to make a decision. He finally resolves to use his power that's too great for one man in order to protect those precious to him, but...