In the fourth stage, the library on the second floor is open. It is located on the floor above the toilet and fireworks room on the first floor. A big ghost appears behind each player. If you turn your head left and right to a certain angle, you will die. There is no limit to moving your aim up and down. If you encounter a teammate's The ghosts behind you will also die. At this stage, communicate more and tell where you are. It is easy to get into trouble if there are people crowded. This stage is mainly to prepare the resources for the fifth stage. The resources are overflowing. There is not just so much. From the second floor Throwing it in from the balcony is generally the safest of all stages.
The fourth stage props: 1 blood talisman in the library on the second floor, 1 key to the liberal arts class on the second floor in the library, 2 blood talismans in the liberal arts classroom on the second floor, and 3 blood talismans in another liberal arts classroom next to it.