Things that are most common in a horror.

Strange noises outside that you should not check out but you do.
Alot of running around a massive house.
When the atmosphere get's quite, you no the 'killer is behind you'
Blood and violence.
Creeky door's that lead to empty places. Do not enter them!
Bad things happen at night.
Car's break down.
Rural settings.
Dead people pop up alot in random places.
When your asleep, your most likely to die.
When your drunk your sure to die.