Isekai Cheat Magician

Word reaches the Royal Capital that the King's younger brother has finally reading his troops for an attack. As the battle draws closer minute by minute, Taichi tries to convince Rin to stay away from the battlefield, yet she displays her strong resolution to fight alongside him. After learning of Rin's resolve he vows to himself that he will protect her.

After driving off the army of the King's younger brother, King Gilmar rewards Taichi and the others are with weapons from the royal treasury. Taichi, Rin, and Muller head down to the training grounds to test out their new weapons. However, Taichi grows ill along the way and goes downton by himself to buy some medicine. There he encounters Cassim, set on revenge, who forces him to accept a duel...

The King's brother, Dortesheim has declared war on Elistain Magic Kingdom, and finally waged a formal battle on the plains of Marwalt. The Kingdom has dispatched its soldiers against them, accompanied by Taichi and the others. Rin, Muller, and Lemia all face their own battles against strong opponents, while Taichi storms the enemy's main camp and takes action to end the war. Yet during the intense battle, the Kingdom's Cardinal, Lodra, is meeting with a mysterious person in the cathedral...

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...