When an industrial accident in Cloudsdale results in a massive release of construction-grade fog, the Weather Department calls upon its certified fog specialists to handle the disaster response. Sadly, none of the experienced specialists are available, so the job falls to Fluttershy, who has no experience and only earned the certification to get a tax write-off. Now, with the fog threatening Ponyville, she will have to step up to the task of supervising ponies...or face the wrath of the Equestrian Revenue Service.
- Accidental Misnaming: Greg tends to do this, most often with Pencil Pusher. This includes narration when he's the character in focus at the time. When Luna refers to Pencil Pusher by name, Greg even thinks that she got it wrong.
- Aerith and Bob: In a world of Pencil Pushers, Hard Hitters, Fluttershys, Rainbow Dashs, Celestias, Twilight Sparkles, Big Macs, Raritys, Bon-Bons and Flywheels, a name like "Greg" looks really alien and awkward.
- Alliterative Name: Pinkie Pie, Pencil Pusher, Hard Hitter, and Five-C, or "Central Cloudsdale College Correspondence Course".
- Apologises a Lot: At one point Fluttershy spends thirty minutes apologizing to the mayor, then apologizes for apologizing so much.
- Be Careful What You Wish For: In the epilogue, we learn that Greg's plan to be put in charge of the Personnel Department went off without a hitch. Unfortunately, without Pencil Pusher around for him to bully, he's faced with the horrifying prospect of actually having to do his job.
- Beleaguered Bureaucrat: Pencil Pusher starts out as this, though he seems to be transforming into a Badass Bureaucrat.
- Big Damn Heroes: Fluttershy! To the surprise of Rainbow Dash that she personally volunteers to leads the rescue mission of the Cutie Mark Crusaders using her fog suit, along with Dash and Thunderhoof.
- Big Disaster Plot: As mentioned in the synopsis at the top of the page, the entire plot revolves around the response to a major disaster.
- Bilingual Bonus: The company that developed the clouds in the first place is called Caligo Manufacturing. "Caligo" is Latin for "fog."
- Call-Back: Pinkie's flying machine makes a return appearance.
- Tom the boulder is used in the Cutie Mark Crusaders' human trap.
- The Chains of Commanding: Fluttershy really doesn't enjoy being put in charge.
- Classy Cravat: Rarity outfits Fluttershy with one of these to make her look like a proper authority figure.
- Contrived Coincidence: Lost in the fog and suffering from hypothermia, Pinkie wanders onto her family's rock farm.
- Conspiracy Theorist: Bon-Bon is convinced the fog is a human plot. Unfortunately, she shares this belief with the Cutie Mark Crusaders, whose naiveté is clearly leading them towards disaster. Again.
- Corrupt Bureaucrat: Greg, Pencil Pusher's boss. To the point he's actively working to subvert Fluttershy's plan just to "win" at office politics.
- Crazy Survivalist: Bon-Bon's preparations for the impending human invasion include an enormous, magically-sealed, steel-reinforced bunker located beneath her candy shop (and several rental properties adjacent to said candy shop).
- Cutting the Knot: As soon as Applejack gets wind of the Love Dodecahedron being built by Poor Communication Kills between Fluttershy, Rarity and Rainbow Dash, she drags all of the offending ponies to the library and tells Fluttershy that Pencil Pusher likes her, cutting through all of the misunderstandings. Rarity objects strenuously to this, since she Thinks Like a Romance Novel. Applejack doesn't care.
- Dark Secret: Throughout the first part of the story Fluttershy's thoughts frequently imply that there is a problem with her fog certification. We eventually learn she took her courses in fog management from an unaccredited university and that she was using her fog specialist credentials to cheat on her taxes. Although as it turns out, she still honestly passed the Department of Weather's certification test and was actually just taking advantage of a legal tax incentive. Despite her fears, she is genuinely the most qualified fog expert available to deal with the current crisis.
- Deuteragonist: Though Fluttershy is the focus, Pencil Pusher has been nearly as prominent.
- Extremely Short Timespan: Based on the chapter titles, the entire story (minus the epilogue) takes place in slightly less than 72 hours.
- Fog of Doom: The titular fog. It's a miles-wide sphere of cloud that simply can't be manipulated and will eventually set "solid". Plus, the interior of it is cold enough that prolonged exposure can freeze Earth Ponies to death. Since it's spread itself over a large area of farming country, it's become very disruptive and has to be gotten rid of as quickly as possible.
- Four Lines, All Waiting: The initial A-plot is the fog. So far so good. Then more plots stat piling in, including Pencil Pusher's crush on Fluttershy (which spirals into a bizarre Love Dodecahedron), Bon Bon and Lyra's belief that humans are in the fog and their differing views on said humans obviously spiraling towards disaster, the CMC's own plot about human interaction gained from overhearing Lyra and Bon Bon that's obviously spiraling towards disaster, the internal politics of the Department of Weather and Greg's assholery (and if Greg'll ever get any true comeuppance), Fluttershy's tax problems (later resolved), and probably more. A couple of chapters have FOUR plots all running concurrently, with the fog plot being the one most delayed at the time.
- Fun with Acronyms: The Society for the Prevention of Human Exploitation in the Realm of Equestria, or "SPHERE" for short. The name also conveniently uses Ambiguous Syntax to cover both situations in which humans are exploiting Equestria, and being exploited by Equestrians.
- Gone Horribly Wrong: Caligo Manufacturing was working on a new industrial cloud formula, one that is much more resilient and almost impossible to disperse compared to normal clouds. It works so well, the tanks can't hold it and the whole mixture becomes a fog bank. The whole story circles around how plain hard it is to eliminate it by conventional means.
- Inadvertent Entrance Cue:Bon Bon:: Lyra, even if the humans are friendly, which they wont be, the fog is almost at Ponyville already. Theres no way to make all those preparations youre talking about in time, unless you seriously think that several dozen new members are going to spontaneously appear in the next few hours.(Pinkie Pie knocks on the door. Lyra answers.)
Pinkie Pie: Hi! Is this the meeting place for SPHERE?
Lyra: Um... yes...
Pinkie: Oh, good! Say, would you guys be interested in getting several dozen new members in the next few hours?
- Intimidating Revenue Service: The Equestrian Revenue Service, run and staffed by Princess Luna's Lunar Guard. The threat of investigation by them is what initially drives Fluttershy to work on the problem.
- Greg, Pencil Pusher's boss.
- Hard Hitter: While not corrupt like Greg, he is rather pushy, and his own coworkers think of him as a jerk whose more concerened about his own position. Not that he cares about their opinions either way.
- Kill It with Fire: Fluttershy's first plan to deal with the fog. Applejack specifically calls the plan this.
- Laser-Guided Karma: While giving Applebloom and Scootaloo her What the Hell, Hero? speech over making Derpy sick, Sweetie Belle inadvertently sets off their human trap, resulting in the two unrepentant Crusaders getting caught in it.
- Also happens with Pencil Pusher and Greg. Pencil Pusher is rewarded for his hard effort in pushing the bureaucratic side of things through with some well deserved rest, a day of the royal treatment (courtesy of Luna) a promotion to his boss's job, and a date with Fluttershy at the end. Meanwhile, Greg, who does nothing except act like a Jerkass Obstructive Bureaucrat, gets browbeat by Pencil Pusher threatening to report him to his boss, then by Luna herself personally coming to oversee the bureaucracy goes through on behalf of Pencil Pusher, and in the end he does get a promotion, only for him to realize too late that he'll be in a department where he can't bully anyone else into doing his work.
- Love Dodecahedron: Pencil Pusher has it bad for Fluttershy. Fluttershy has shown some minor signs that she might return his feelings. Rainbow Dash and Rarity have been indulging in Shipper on Deck meddling to get Fluttershy and Pencil Pusher together. Because of that meddling, they have accidentally convinced Fluttershy and Twilight Sparkle that they (Rainbow Dash and Rarity) are also attracted to Pencil Pusher. Fluttershy and Twilight Sparkle carelessly mentioned their mistaken belief in front of Spike, who now worries that Pencil Pusher is his competition for Rarity's affections.
- Eventually subverted: The whole mess comes to an abrupt end when Pencil Pusher assures Spike that he doesn't fancy Rarity, and when Applejack tells Fluttershy about Pencil Pusher's feelings and about Rarity's and Rainbow Dash's meddling. It's amazing what a bit of direct and honest talk can accomplish.
- Mythology Gag: From September 2 12:30 PM, when Twilight remarks on Fluttershy's competence, it references the Keep Calm and Flutter On episode of the original show, where Fluttershy does handle Discord:In fact, if Discord ever shows his face around here again, it might be a better idea to put you in charge.
Okay, now youre just being silly.
- Nice Job Breaking It, Hero!: Two examples so far.
- Flywheel, the worker at Caligo Manufacturing who went to use the bathroom, asking the janitor to look over things while she was gone, and forgot that the special nature of this fog meant that the usual gauges were inaccurate. This led directly to the titular Fog of Doom being unleashed.
- Bon-Bon, who was silly enough to make her paranoid rant about humans where the Cutie Mark Crusaders could hear. With their typical lack of foresight and overenthusiasm, the trio are now determined to catch the non-existent humans they think are hiding in the fog. The ramifications of this are quite obvious in advance.
- No Antagonist: The main plot is a straight up disaster story. The closest thing the story has to an antagonist, Hard Hitter, turns out be a Red Herring when it's revealed that Fluttershy's Dark Secret only exists in her head. He goes off in search of bigger game.
- Obstructive Bureaucrat:
- Greg, once again.
- Also, the unnamed claims adjusters at Caligo's insurance company, who insist that they withhold trade secrets related to the composition of the fog, or risk losing their industrial espionage coverage.
- The Only One: Fluttershy would much rather have had another fog specialist deal with this, but there is a serious shortage of fog specialists and all the others are unavailable. So Fluttershy has got to do it.
- Poor Communication Kills: The Cutie Mark Crusaders don't actually know that the fog is lethally dangerous to ponies—especially to foals their age— since nobody is willing to scare them by telling them the truth. Because of this, and because they don't want to get in trouble for listening to Bon-Bon's crackpot theories, nobody knows that the Cutie Mark Crusaders intend to go into the fog.
- Punctuated! For! Emphasis!: Well, Applejack drawled, the basic idea can be summed up in four words: Kill. It. With. Fire.
- Pun-Based Title: "Flash fog" instead of "flash flood." There is actually a phenomenon known as flash fog, which is fog which forms and dissipates rapidly.
- Red Herring: Two of them.
- Hard Hitter's investigation into Fluttershy's credentials was a misdirection to hide the fact that Fluttershy's Dark Secret was all in her head.
- The Love Dodecahedron between Pencil Pusher, Fluttershy, Rarity, Rainbow Dash, and Spike was merely an elaborate set-up to allow the Cutie-mark Crusaders to escape the party when Spike went in to talk to Pencil Pusher. The Love Dodecahedron fizzled out once its purpose was served.
- Rube Goldberg Device: The Cutie Mark Crusaders' human trap, which turns out to be so complicated that Sweetie Belle belatedly realizes that the trap is useless unless a human happens to stand still long enough to get caught in it (about five minutes), which admittedly is exactly what happened to Apple Bloom and Scootaloo.
- Shipper on Deck: Rarity eventually decides to help things along between Fluttershy and Pencil Pusher. Rainbow Dash, meanwhile, supports the idea as well, but thinks that Rarity is pushing too hard.
- Shout-Out: Purple dragon Spike walks into the party to talk to Pencil Pusher, who briefly mistakenly calls Spike by the name of another purple dragon.
- Start X to Stop X: After working so hard to keep the fog from consuming Ponyville, Fluttershy's plan ultimately involves deliberately letting the fog pass through Ponyville into the Everfree so that, ideally, the forest's wild magic will cause it to dissipate.
- Terse Talker: Greg speaks this way in order to sound authoritative and intimidating. It seems to be effective enough to obscure his overall incompetence to most ponies. (Unfortunately for him, Princess Luna is not most ponies, and she calls him out on it.)
- Thinking Out Loud: In September 2 8 16 AM, Pencil Pusher muses out loud, about talking to Fluttershy when they don't have a reason to talk, and this trope is lampshaded:But how do I bring up any sort of topic without it coming off as awkward? Pencil Pusher said aloud.
Well, for starters, you can try not talking to yourself in public, a nearby stallion replied sarcastically.
- Thinks Like a Romance Novel: Rarity does, and after Applejack finishes Cutting the Knot, she briefly but succinctly spells out to Rarity why this is a really poor choice of perspectives.
- Title Drop:Whoa, that things moving pretty fast. Its kinda like a flash flood, only with fog instead of water. I guess that would make it... what, a flash fog, then?
- Unfortunate Names: Seen in this exchange, likely a reference to "Ponyville Confidential":Mayor Mare: Elected officials cant afford to apologize for their opinions. Not if we want to be reelected, at least. They create openings for accusations of being wishy-washy.
Pinkie Pie: But I thought Wishy Washy just got elected to Parliament last year.
Mayor Mare: (groans) Dont remind me.
- Unusual Chapter Numbers: The title of each chapter indicates the date and time at which its action begins. Some of them are only separated by a few minutes.
- We ARE Struggling Together: Since the day it was founded, SPHERE has been divided between Lyra's faction, who think that humans will be wonderful beings that need to be protected from Equestrian exploitation, and Bon-Bon's faction, who think that humans will be terrible monsters that will try to exploit Equestria. When it was just the two of them, it just led to constant arguments. Now that more ponies are starting to actually consider the two's claims seriously, the approaching factionalism is quite obvious.
- What the Hell, Hero?: Sweetie Belle gives her two fellow Crusaders this in regards to giving Derpy an ipecac-laced muffin so that they could escape the party to check on their human trap.