As The Gods - Will
It sounds like you're referring to As the Gods Will (『神さまの言うとおり』, Kami-sama no Iu Tōri ), the manga (and live-action film) about a deadly series of children’s games forced onto high school students by a mysterious "god."
It sounds like you're referring to As the Gods Will (『神さまの言うとおり』, Kami-sama no Iu Tōri ), the manga (and live-action film) about a deadly series of children’s games forced onto high school students by a mysterious "god."