In honor of nothing in particular, let's do a few dark stories! Check out my thoughts on three creepy, macabre, or otherwise lightlesshearted stories, below the break.
Memories of Shadow, by Distaff Pope
Zero-ish spoiler summary: A career criminal is brought before Celestia after being caught. There, she discovers why there's no such thing as a "career criminal" in Equestria.
A few thoughts: There's something about "Celestia mind-rapes ponies into complacency" that speaks to authors, it seems; this is a theme I've encountered with some frequency in stories. But where some stories would use that to explore Celestia as a character, or as a means to explore some ethical point, this story exists almost entirely to develop its main character. That ends up being something of a weakness, I think; it means that the story's source of darkness is more or less ancillary to the narrative focus--though the two are obviously heavily intertwined, neither particularly requires nor utilizes the other. There's a lot of strong imagery in this fic, however, and if Silent Shadow is a fairly one-note character for how much attention is lavished on her backstory, it's also a single note that finds the sweet spot between "able to evoke empathy" and "definitely not a good pony."
Recommendation: If you're tired of "Celestia mind-rapes ponies into complacency" as a story concept, this doesn't bring anything to the table liable to win you over. If you're actively looking for something in the mental-destruction category, however, this is a solid pick for readers who appreciate strong use of motifs in their fiction.
Wild Card, by Akumokagetsu
Zero-ish spoiler summary: Trump card comes home to his hut at the edge of town late one night.
A few thoughts: This was originally published on October 30th, and I feel like it's the kind of story that can only be properly appreciated in the context of being a day-before-Halloween fic. This is a barely-1k, atmosphere-heavy story that pretty much just exists for the sake of its "reveal" at the end. There's nothing else here--no attempt to connect the story to Equestria in any meaningful way, among other things--but as a quick, easily-digestible piece of spookiness for an audience lacking any need for setup or justification, I think it's fine.
Recommendation: So... if you're looking for a spooky microfic, this will do nicely. If you aren't specifically seeking that thing, however--if you want a story with a "story" beyond some ominous scene-setting and its reveal--this would be a poor choice.
The Smile, by ToShyShy
Zero-ish spoiler summary: There is a reason fillies and colts are told to stay out of the Everfree Forest--there are creatures that live there, and no mere animals they.
Recommendation: Another Halloween-time fic, this one more from the creepypasta school of writing. It got off to a good start, using the Everfree's foreboding status to excellent effect, but subsequent additions, both tonal (e.g. AJ's death being of the "by the way, she's gone now" variety) and temporal (building a reveal around an undeveloped roll of film in a near-modern camera feels too modern for Equestria, though I'm sure plenty of people won't find it as eye-catching as I did) made this feel pretty generic. Still, it's a disconcerting enough core idea, if you're looking for something creepy to imagine.
Recommendation: This would be a good choice for the creepypasta crowd, but probably doesn't have much appeal outside of that audience.