The Holy Grail War Begins in the Strength Classroom

One day, Xuan Hao received a mysterious admission letter and walked to the mysterious high school. When I entered the school, there were three more marks on the back of my hand! Moreover, there is an additional system where the dragon can see its beginning but not its end! "I thought I was escaping the whirlpool struggle of forces, but unexpectedly I fell into an even bigger whirlpool!" Weird teachers, strange hierarchical system, ulterior motives and a constantly changing world! First World: Welcome to the classroom, the Holy Grail, of strength supremacy. The Second World: Demon Slayer: Kimetsu no Yaiba, Attack on Titan. The third world: Naruto, One Piece. ... This novel and its characters are purely fictitious. Any similarity is purely coincidental and should not be imitated.