In the film Clown Train, the sound does contribute a lot to the atmosphere. We can hear the sound of the train coming and the brake, even though the screen is still all blacked, but we can imagine there will be a train on screen later. As the atmosphere is going to be creepy, the clown appears on screen and the lights in the carriage are flashing, and the sound of electric current build up the atmosphere to be horror. Also, the laughter of the clown is creepy enough in the conversation. And of course, the sound that illustrates the train is driving away at the credit scene would contribute the atmosphere that is the horror mood is going slightly and implies the story is going to be ended. These sounds would make me to recall the series of SAW, there are many sound effects successfully to build up the creepy and horror atmosphere to scare the audience.