Unseen/Seen Entities

This trailer uses both seen and unseen entities. 
The part of this trailer that shows an unseen entity is the scene with the rocking horse.

This scene is really effective because we begin to wonder what is rocking the rocking horse. Also, the fact that we cannot see what is doing this, puts nearly all of our focus on the sound. 
Seen as sound is very important in horror films, it makes sense to put a lot of the focus on it.


Pros of using an unseen entity;

• No need for an extra actor
• More focus on easier things; ie sound
• Seems more eerie
• No special effects/makeup etc needed
• Possibly scarier as we cannot see what is causing all of the problems 

Cons of using an unseen entity;

• Can look tacky
• Difficult to be different from other films 
• If the sound isn't perfect then it would not have the same effect

However, this trailer does also have a see entity.

Although it's effective to have all of our focus on sound, I think that this is also a perfect example for why we should use a seen entity. 
Generally, it's the surprise element that makes it much more exciting. In a supernatural horror, we do not expect to see the thing causing all of the problems and, when we are faced with this, we are surprised.

Pros of using a seen entity;

• Surprise factor
• Chance to do something completely different and new
• Effective without sound

Cons of using a seen entity;

• Hard work to think of a new idea
• Makeup could be problematic 
• Having to rely on another actor could cause further problems 
• Once the audience has seen the killer once, it might not be as scary after that