Mondaiji-tachi ga Isekai kara Kuru Sou desu yo?

Synopsis

The Gift Game against Perseus involves invading their fortress and only those who can reach Luios before being detected shall have the right to challenge him. With those rules in mind, Izayoi comes with a plan of having Asuka distract most of the guards using the water tree that they obtained while You gives way to Izayoi and Jin as they sneak past them. Before Izayoi and Jin confront Luios, they needed to have one of the replicas of the Hades Helm, a helmet used by the guards which turns the wearer invisible, to avoid detection. After obtaining one which Izayoi uses, the leader of the guards attacks them, wearing the real Hades Helm which gives You a hard time detecting the enemy through her normal means of detection. With the help of You's echolocation ability, Izayoi defeated the enemy and obtained the real Hades Helm which he gave to Jin. As they continue to proceed with their plan, Izayoi and Jin found Luios in a colosseum, beside Leticia, who is turned into stone. Instead of confronting him, Luios unleashes his trump card, Algol the Gorgon, a former Demon Lord under his control. Algol turns all outside the colosseum including Asuka and You into stone and attacks Izayoi, who easily overpowered it with his strength and defeats it by destroying its gift with his Unknown ability. While acting as a judge, Black Rabbit can't believe that someone has both the ability to destroy the world and the ability to destroy gifts which is impossible. Luios admits defeat and asked them to take Leticia, but Izayoi has given Luios a chance to fight back by challenging him to a fist fight, raising the stakes of the game where Perseus has to wager their banner when they lose, for Izayoi to ensure that the Perseus community is destroyed for good. In the end, Izayoi won against Luios. After they defeated Perseus, Izayoi and the others took Leticia back in their community as a maid which Leticia agreed as a gratitude for saving her. As the No Names celebrate their victory outdoors, Black Rabbit announce to them that Perseus is exiled from Thousand Eyes and is forced to taken down their banner, the Perseus constellation, from the night sky. Everyone from the community made their wish as they watch the stars from the Perseus constellation falls. Izayoi gains another goal and that is to put their banner in the sky. While the No Names celebrate their victory, another letter from an unknown sender is seen on a table.

(Source: Wikipedia)