The first interior scene bestows an uncomfortable sense of trespass by not only having one stumble down the middle of a country road at night, but by forcing the indecent act of rubbernecking at highway accidents. The extra disorientation of forcing one to go through a surrounding so familiar yet literally turned sideways will only add to the distress.
The pile of bloodied bodies clogging the seats of the school bus isn't just the morbid setting, they provide the distraction. Like powerful rockets, the best scares are often engineered to be two-stage.
A bloodied ScareActor camouflaged into the pile is present to feign death until a guest gets within grabbing distance. Then, with a sudden spasm, the boundaries of that grabbing distance are explored. Even if you rightfully assume or even just suspect that one of the bodies in a pile of mannequins is live, there is always that frenzied internal monologue that adds to the adrenaline of the situation. It's like you're trying to decide if it's the red wire or the blue wire you cut on a ticking time bomb that detonates not shrapnel but fright.
And won't a sharp-eyed guest feel quite accomplished when they cleverly discern which of the bodies in the pile is the real one? They might even pause to taunt and mock, just to announce to the world how clever their deductive abilities are.
That's when another ScareActor slams into the window right above their heads. Indeed, they will likely show how clever they are by sensibly dropping liquid or solid ballast before fleeing.
Windowbanging is quite the tried-and-true haunt technique. It's often expected. However, the novelty of the set configuration will undercut this expectation when installed overhead. (An extra layer of clear ballistic film slinging the plexiglas pane tight into the frame should help ameliorate any safety concerns.)
When arranging the bodies, they should be affixed together into a "corpse sleeve" through which the ScareActor can slide when doing changeouts. An internal configuration that keeps the majority of weight off of the person would be much appreciated and even necessary, given the multitude of hour-long shifts throughout the night.
Additional scare opportunities can be garnered by bloodied Scouts lurching at the guests from behind the trees in the woods or from behind the rear hatch ripped free from the bus. The crackling sounds of a nascent brush fire inferred by the uplit fog machine output will also add to the anxiety.
Monday: Meet Scout