Warning: Wall of text. Also feel free to take some, all, or none of this. Just an fic I never got around to writing.

Cataclysm (Very rough Title): The fic takes place in an AU after season 1 (before season 2 starts). About the loss of magic in the world.

Set up: The fic is told from pony's perspectives. The fic starts off with Twilight's perspective in which she has Spike send her most recent report to Celestia. The report hits Twilight on the head, and she scolds Spike for playing around. Before he can explain, there is a knock on the library door. It is Rarity telling Twilight that Granny Smith has died. From there it cuts to the future, where society has turned radically different. It is revealed throughout the story that Magic has been being drained from the world. The first few weeks old ponies dropped like flies (magic is connected to life force). The princesses have not been seen in a while, day and night cycle has continued but at a slower rate, days and nights lasting longer and longer as the story goes on. Cloudsdale has fallen (found out through some survivors), where the magic that holds it together dissipated, many that lived there ending up falling to their death. Earth ponies lose their magical connection with the earth and strength, making farming significantly more difficult, pegasi cannot fly as well due to their magic making them lighter in flight, and unicorns, more obviously, cannot use spells. Basically everypony is equally weak with few exceptions, as those with stronger magically connections have been able to retain more. AJ still stronger than most, Twilight can use some spells, and RD can fly slightly faster than a sprint (most pegasi at this point are ground bound), but even these take lots of energy, especially true for Twilight and RD.

1st Arc: Ponyville now has 2 major factions: AJ's farmers, a group of farmers and friends that lived on a fraction of AJ's farm that has been walled off with apple tree logs (it is worth noting that at S1, AJ is one of the most respected ponies in ponyville and holds a lot of influence) ; Ponville police and medical, stationed in ponyville general and includes the ponyville police, the general staff, and civil servants most notably Mayor Mare. AJ's farm deals with supplying everyone as best they can with food, which has become more difficult to grow, while Ponyville police do their best to keep the peace, but their influence is slipping. The arc starts with Twilight's perspective, who is experimenting in AJ's shed. On a table in the center is a potted seed which she hopes to grow quickly through the use of magic. Through many experiments she has found that gems (in enchantments and catalysts) hold most of the magic channeled into them and this is an experiment for a practical application of it. She appears to be getting close, but it blows up in her face, literally. She exits the shed to air out the smoke as she notices that she's on schedule for food escort today and decides not to experiment any more for now as it would take up too much energy. She accompanies AJ and a few others to deliver food to the square, where they hand it out in rations. Some ponies are desperately watch them, but AJ shows enough force (shouting 'stay back' etc) that no one makes a move and they all take their rations with relative ease. Next perspective is Pinkie, she notes that morale has been falling and that she tries hard to keep everyone happy. She hears a small explosion as Twilight exits the shed (this perspective is concurrent with Twilight's). Pinkie remarks that she hasn't seen Twilight smile in a while, and she tries to cheer Twilight up but is brushed off by Twilight who is getting ready for escort duty. This perspective is for pinkie to go around introducing the town and it's ponies' states to us; ending with Mayor mare, who feels useless due to her inability to unite ponyville. RD is next exploring the white tail woods for supplies. She carries an iron pipe that she become a favorite of hers. RD runs into Close Stitch, an mid aged jealous mare that is a 'rival' to Rarity. She also finds some supplies in a tower, including some flares and a flare crossbow. The rest of this arc is less detailed (and I also realize how long this description is for just this part so I'll try to keep it short from here on). Mayor Mare begins investigating some mysterious disappearances that she does not report in order to solve and win back the ponies' influence. She happens upon a killer who has recruited other ponies (who were introduced earlier, Close Stitch, as one example) to his cause, basically anarchy, he uses them by promising the food that AJ keeps "to herself and her friends while we starve". Mayor Mare gets captured and killed. They eventually launch an attack on AJ's farm, causing the walls to come down, and while they ultimately fail, most of them dying in pathetic ways as they were just being used, they did enough damage that convinces Twilight to find Celestia.

2nd Arc: Twilight and RD begin their journey to Canterlot. They are best for the mission due to their magical ability and leave with food and other supplies given by AJ. AJ also gives Twilight a knife passed down through her family. It comes with an enchanted holster that keeps the knife sharp and also turns the knife and holster invisible when together. They come across some travelling yak merchants, though they are wary, they trust them and decide to swap news (this would be a good place to put some foreshadowing). Twilight and RD decide to make camp so that the yak's can pass them (both parties heading the same direction). The next day, they find the Merchants' supplies but no merchants. Further down the path, they notice that someone has been watching them. This continues until just before night, the decide to hike further before they make camp. They pretend to go to sleep, but are soon taunted by some bandits clearly enjoying the sport of it. They attempt to flee but are split up, at one point a stallion is atop Twilight, taunting her again that gonna kill her. Twilight attempts to reach for the knife that is on the holster on her hindleg, just before she can get it the stallion is suddenly gone. Twilight finds RD and they realize that the forest is silent. They pack their supplies and decide to walk and stay up. They eventually find an abandon camp, which they determine to be the bandits' camp, although it is empty. They both eventually collapse from exhaustion near the camp. They wake up in a bed in a cell. It is revealed that they were found by some residents of a small town, and they want Twilight and RD to stay. The residents talk about their upcoming feast from a bountiful harvest. There is also mention of Cereus, a pony who runs the settlement, but is asleep currently. Twilight decides that they should stay for the feast and leave first thing in the morning. They agree that if either finds something suspicious they would notify the other immediately, RD takes the flares and Twilight would have her spells for a similar effect. RD helps with the preparations and feels like something is off. Later revealed that their harvest seems impossibly small for a feast. Twilight meets Cereus, who is revealed to be a bat pony, they talk and it is revealed that Cereus looked for Luna but was not able to find her or Celestia, he stopped searching when he found the town near collapse and decided that he needed to save them with his military experience. Night time comes and their feast is revealed to be the bodies of the bandits cooking near a huge bonfire. Cereus recognizes Twilight's horror but tells her that that he saved the town with this method and that she is lucky, not only cause she 'came at a good time, you could join us' but also because he personally saved her; he was responsible for getting the bandit stallion off of her. A flare goes off. Cut to RD, earlier, just before night time, she breaks off from the group. She does an investigation and finds a barn that has cold air coming from it. She finds preserved bodies in the barn, refrigeration achieved through enchanted gems. RD takes off and set off the flare. Cut back to Twilight. Twilight, Cereus, and one of the residents are distracted by the flare. Twilight is the first to react realizing what it means. She stabs Cereus and pushes the resident into the bonfire causing chaos in the town as it falls over. Twilight begins to run in the direction of the flare, into the forest. Cereus catches up decently fast, tells Twilight that she can't hid from him due to his ability to see in the dark, he also tells Twilight that he purposely chose that town due to it's positioning. Normally the town was unknown due to the train taking traffic away, but the town was right on one of the few foot paths to Canterlot, where Cereus expected most ponies to want to go to. She makes it out of the forest, morning is barely starting. RD and Twilight begin to fight Cereus but he proves to be a difficult opponent. At one point he is beating up RD when Twilight tackles him. Cereus gets on top with his superior strength. Twilight feels around for something to help her, grasping in telekenisis what she believes to be the pipe RD carries around and swings it at Cereus. Cereus flinches briefly, before it comes into contact onto him. Realizing it's not iron but instead plastic he begins laughing believing he has won. Twilight realizes it's the flare and uses the last of her energy to ignite it like a makeshift flashbang. It cuts briefly to Cereus POV that would begin "The whole world turned white". He suffers from sensory overload from the flare and his sensitive eyesight. He swipes wildly hoping to hit Twilight but his posture changes drastically. He even attempts to hear her but the sensory overload has made it difficult to concentrate. Twilight hits him over the head with the pipe and "The whole world turned black" would be the last part of Cereus POV. Twilight gathers her bearings, and realizes that they are near the train tracks to Canterlot. She sits down in exhaustion near RD and it begins to snow for the first time this year.

Third Arc: Twilight and RD make it to Canterlot where they find the city is a warzone, between Blueblood's army and Shining Armor's guard. Blueblood believes himself to be the rightful ruler, who can lead the ponies back into proper society. Shining Armor meets with Twi and RD and explains that him and the guard protect Cadence who was not crowned princess officially. but is an alicorn. Twi and RD are captured by Blueblood who relays excitement to his followers that he captured two 'elements' to be used as leverage. Blueblood's second in command, Fancy Pants backstabs him and coups Blueblood's army before surrendering to the guard. Fancy Pants explains that he lost faith in Blueblood, but is partially responsible for his rise. Twilight and RD meet Cadence who is revealed to be bedridden. Cadence uses her magic to try and keep the sun and moon in balance despite not being attuned like Celestia and Luna. This robs her of most of her energy. Cadence also tells them that she can feel another energy, controlling the sun vaguely. She believes it could be Celestia, but knows that the possibility isn't worth it cause Canterlot needs the guard in the aftermath. Cadence tells them where it is, far North of Canterlot.

Finale: Three weeks later, Twilight and RD make it to the magical signal Cadence told them about (note the whole story takes place about the span of 7-9 months). It is a cave. Inside they find Celestia and begin asking for answers. Celestia asks Twilight if she believes in the story of the first Hearth's Warming. Of course, she believes part of it is rooted in truth. Celestia confirms that it is. At this point they notice that behind Celestia is a black sphere. RD asks where Luna is. Celestia sighs, she tells them that immortality is more of a curse than a gift. She lists the cons and then says 'especially the price of immortality'. They question her further, and she goes on to tell them that the first Hearth's warming (which was really just a (re)uniting of the three races, was cause not by Windegos but by magic dying out. She tells them that the price of their immortality was the magic of the world. Celestia and Luna ruled over society before Equestria, found a treasure which gave them immortality and they awoke generations later to a small society. ("Ever wonder why the first Equestrian flag had the two sisters? It was not an historical error"). They eventually found out that they were the 'Windegos' and the cave they are in was where the first Hearth's Warming took place. Celestia feared this day would come when Luna returned to her original form after the elements purged NMM from Luna. Twi is shocked and RD is mad, but Celestia threatens them if they try anything. At this point they notice that Celestia is like Cadence, skin and bones. Celestia tells them she tried to mitigate the damage by offering her magic, but that she 'saved enough to deal with anyone that would stop my sisters return'. Twi asks what the repercussions are. Celestia says the world's magic would take many generations to recover to the way they were before, but society would be livable when Celestia and Luna came back as rulers, which would take a few more months for them both to recover fully. RD would get angry that Celestia would assume they could just return to the society they destroyed. The story would end with Twi and RD heading back to Ponyville silently after giving hints at either them killing Celestia/Luna or accepting society.

Bonus: One idea I was toying with but thought might be too dark was that in addition to Luna absorbing all of the magic, she absorbed the souls of all that died, as lifeforce and therefore souls were connected to magic. This would mean those that died during the duration of the story would not go to any form of the afterlife.

Epilogue: There is a short scene that takes place a few days after Twi and RD leave Canterlot, where Sunset Shimmer steps out of the mirror. It would set up nicely for a sequel, in which Sunset is the most powerful pony in Equestria until Luna's rebirth. Either she could be good or bad, but if I had to say, I would've written her to be good and ultimately question her relationship with Celestia when she finds out the truth.