Stolen from Rod Serling:
"There is nothing in the dark that isn't there when the lights are on."
It's ambiguous, either horrifying or reassuring depending on how you take it. Or perhaps both at once.
What kind of story would you write with such a prompt?
Could go a lot of different ways with a prompt like that. The big difference between seeing things in the dark and seeing things in the light is not what's actually there, but what you perceive to be there. It's all in the way you look at things, which is an idea which you could work into any number of stories. Given the light and dark thing, a pre-Nightmare Celestia and Luna story could work, taking the theme of everything being the same, light or dark, in that the world/Equestria is the same no matter the time of day, and using it to present the attitudes of ponies in day and in night, particularly to the princesses of day and night themselves. There is nothing which vanishes from the world when day breaks, but how the world is viewed changes, and that can make all the difference. I dunno, I'm just throwing ideas at the wall to be honest. Bit miffed at the lack of comments, would have expected more given how interesting and accessible the topic is, but ah well.
Well, since darkness is—by one definition—a lack of light, photons aren't there when the lights aren't on. Plus there's the whole quantum superposition… thing… with the cat… so there are the possibilities of what's there when the lights are out. Don't get ol' Howard Phillips started on that second one, no siree.
In other words, are the monsters under the bed only real when they can't be seen or heard?
You could write a Luna story around that prompt--the realization that what makes her as a pony special during the night doesn't go away during the day, and her integration into pony society. Or, the darker flipside, which would basically be Luna bitterly responding "No, but there is someone who goes away when the lights are off."
Rod Serling was the best.
I'd probably go horror. A character tormented by shifting shadows trying to get the lights back on, convinced something else is in the house. A the trip continues the protagonist begins to think whatever it is is there because of the darkness. The final stretch would be the basement (to get to the fusebox) which would be full darkness. The lights are restored, everything's fine.
Then it's not. Maybe the protagonist even gets thanked for turning the lights back on right before it happens. The exact details of 'it' are best left to the audience, but just enough is given to be sure it's terrible. Turns out lights are convenient for monsters, too.
I was just struck by another thought. Suppose the monsters under the bed only exist when the lights are out. From their perspective, the world keeps abruptly changing, as they have no perception of events occurring while the lights are on. Things move suddenly from one spot to another, or disappear, or abruptly appear out of nowhere.
Just because you can't see the terrifying creatures are hiding in the dark, doesn't mean they're not completely invisible altogether.
3693568 Aye. If anything, it's people that are different.
3693608 I bet you could do both in the same story, even!
3694823 Yeah that's the horror inverse. Anything that's there in the dark...is there when the lights are on, too.
3693590![:derpytongue2:](https://static.fimfiction.net/images/emoticons/derpytongue2.png)
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I think you're missing the point of the prompt
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Tomato, potato…![:pinkiecrazy:](https://static.fimfiction.net/images/emoticons/pinkiecrazy.png)
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