WMG / My Little Pony Friendship Is Magic Setting Changelings

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Guesses about the Changelings, their nature and their history:

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Culture and Society

The Changelings have their own kingdom and culture.

This is indeed possible due to them, and not just Chrysalis, showing intelligence and understanding beyond that of a presumed "hive mind", because if that was the case, they would have been able to tell that Fluttershy was passing herself off as one of their own. Their kingdom and culture and society could be revealed to based off that of similarities to Oriental cultures, like Japan and Korea, the rationale for this mainly how Chrysalis' designer, Rebecca Dart was inspired by the work of manga artists Junko Mizuno and Hideshi Hino. Therefore, if we see the Changeling Kingdom in the show it can potentially enable the show writers and animators to explore some East Asian art, architecture and culture. And picture this: Changeling Samurais!

• To elaborate on that: there might be several types of Changelings. The "civilized" ones form couples and subsist on love towards each other. The "subtle" ones are rogues, who spend time familiarizing themselves with one single pony until they can emulate said pony's personality perfectly. When that's done they quietly remove that pony and spend the rest of their lives with the partner. "Feral" changelings are the barbarians of the changeling world, raiding cities, forcefully feasting on the love of others and moving on, leaving the city ruined. Queen Chrysalis is a "Feral" Hive Queen.
  • Alternatively again, Chrysalis is not a Hive Queen at all, but a disgraced and exiled Civilized Changeling who took over a Feral Changeling colony.
    • It should be pointed out that they may not be of a Hive society of any kind, monarchy or otherwise. There is no canon support for the concept other than they appear insectoid and their leader happens to be a Queen, but that does not necessarily make it the case.
• The Changeling Kingdom showed up in "To Where and Back Again", where it was revealed to be an insect-like hive.

Changelings are actually the largest minority in Equestria.

But most of them are law abiding citizens that just use their shape shifting powers to fit it. Since they only feed off of the love that their friends and family feel towards them, they don't really draw attention to themselves.

Changelings aren't a eusocial species, but more like locusts

Chrysalis does refer to the changelings as a "swarm" during her episodes, but eusocial insects like ants, wasps and bees aren't the only insects that swarm. Solitary species like locusts and flies also come together in groups called "swarms", too. Given how complex it can be to extract love, and how hard it would be to scale that on a grand scale as would be necessary for a eusocial species, it's more likely that the natural "state" of changelings is alone or in small clusters of siblings/spouses & children, who nomadically travel and steal love where they can get it. But, every so often, circumstances arise and a particularly bold changeling rises up. Equestria just had the misfortune to see the latest "swarm nucleus" form, when "Queen" Chrysalis took power, drew the rest of the changelings around her, and tried to conquer Equestria.

Changeling castes:

Some hypothesizing on possible changeling biological castes after "To Change a Changeling":

• Royal changelings: Chrysalis and Thorax. The leaders of changeling society. Physically, they are the largest caste — the size of an alicorn — and have larger and more complex horns/antlers than other changelings. They can also wield more powerful magic than other changelings. They are the most long-lived caste, and are quite possibly truly ageless. They are also the ones who produce the next generations of changelings, regardless of the royal's gender.
• Demiroyals/Praetorian changelings: Pharynx. Intermediate in stature, horn size and magic power between royals and other changelings, they act as the royals' seconds-in-command and lead sections and divisions in the larger hive, such as Pharynx being in charge of defense. While not ageless, they have longer lifespans than other changelings.
• Drones/workers/common changelings: the regular kind. They make up the hive's assorted workers, soldiers and civilians. They have about the same lifespan as a pony.

Changelings may be born into a caste, or they may ascend to it from a lower caste, as both Thorax and Pharynx did, either by themselves or with the aid of other changelings: possibly, a high-caste changeling may facilitate the metamorphosis of another, lower-caste changeling. The reason we didn't see any "demiroyals" while Chrysalis was in charge is that Chrysalis is simply not the type of person to share any power or prestige with others is she can help it, and would have made sure to prevent any of her subjects from moving past the drone stage.

In Changeling society, you're siblings if you come from the same clutch of eggs

This is assuming that changelings reproduce like eusocial insects, with the Queen (or King, as the case may be) producing all the eggs in the hive, as opposed to all 'lings being fertile. In this case, while the changelings are aware they're all biological relatives, they consider their brothers and sisters to be the ones that they grew up alongside, which ends up meaning the ones they hatched with. Thus, if you're from the same batch of eggs you're siblings, and if not you're simply fellow members of the hive.

Chrysalis Hive during her rule was similar to Ancient Sparta.

Notice how changelings refer to Chrysalis not as 'mother' but a 'queen'. Similarly, Chrysalis refers to them as her 'subjects', not 'children'. It could be that changelings always mated in pairs, but under Chrysalis's regime, all hive eggs were collected and raised directly under her supervision to ensure complete loyalty to her, and to teach them how to fight and hunt other creatures. Adults hardly got to see or interact with their nymphs after laying their eggs. This cold, detached relationship would only aide Chrysalis in keeping her army focused and concerned only on the hive, and satiating hunger. This theory belongs to Fimfiction user NavelColt who deeply analysed Chrysalis relantionship with other changelings, but I like this theory so much that I accepted it to my headcanon (aside from the bit that has Thorax, Pharynx and Spiracle (Ocellus's mom) as Chrysalis biological children).

Origins

The Changelings are actually what remains of the Flutter Ponies, after their race was twisted by some horrible curse.

Despite their obviously monstrous nature, they still bear many basic similarities to ponies, and have insectile qualities and comparative magic as well. It's possible they were once ponies themselves who were... changed... by something. Perhaps they are all that remain of Flutter Ponies in modern-day Equestria?

• Maybe the Queen was an attempt by the Flutter Ponies to create a Celestia-analogue, powered by the Power of Love. It didn't end well.
• Maybe they're the Unseelie to the flutter ponies' Seelie court?
• Maybe they used to be Flutter ponies until they stood up against Discord and her mutated them beyond repair.

The Changelings ARE Flutter Ponies who were twisted by Discord.

Because doing something like this for the sheer lulz is very much in his character.

• You read Smoke and Mirrors on FiMfiction.com, didn't you?

The Changelings ATE the Flutter ponies.

Which is why there aren't any in the FiM setting. They also ate the seaponies. The reason that the Queen didn't kill Cadence or Twilight is because she didn't want to run out of ponies again.

There are no Flutter Ponies in G4. The closest thing we'll get is Changelings.

Just because.

The Changelings first made their appearance in Story of the Blanks.

You know... As the residents of Sunny Town?

• How did they get the wings?

The Changelings are blanks that escaped

They where twisted in a different way than those who became blanks.

Changelings are aliens.

That's why nopony but Cadence knows about them (Cadence only knows from Chrysalis herself, being her first victim). Their nature allows them to travel through space with no need for spacecraft (like the Zerg Swarm, for example). They invade every inhabited, advanced planet they encounter, feast on the emotions of the locals while wreaking chaos, and leave after slaughtering the whole population, off to the next world. Shining Armor and Cadence's spell didn't just blow them out of Canterlot and Equestria - it blasted them all the way off into space.

They look superficially like ponies for the same reason why many aliens in most media look at least partially humanoid. They know Equestria's language because of either some kind of telepathy, or because the Queen has been masquerading as a pony and preparing the invasion long enough to learn it (the other Changelings may not even know it at all, the only time they speak, they just imitate the sound of Twilight Sparkle's voice).

• But they understood what she said well enough to know it was something worth repeating in context and giving a smug grin afterwards.

• Changelings are aliens in my headcanon as well.

The Changelings came from another dimension.

Specifically, a parasitic dimension where time doesn't flow normally and space is in a constant flux. This dimension "attaches" itself to others and feeds off the emotions, lifeforce and other energies until it is no more then a husk. Then it moves onward.

The Changelings and the alicorns share a common ancestor.

Mostly because all the Changelings had horns and wings, not just their Queen. Maybe Changelings are "fallen" alicorns, or their equivalent of demons?

The Changelings are just that

Snatching foals and replacing them with their own offspring (or possibly full-grown changelings) is their usual MO - overt action like in the episode happens rarely. This wasn't mentioned because the intended audience would never have slept again.

• Perhaps Celestia put a stop to the practice. Would explain why they resorted to such drastic measures.

Changelings used to be subjects of Princess Luna.

Way back in the backstory, Luna turned into Nightmare Moon because she felt she wasn't getting enough love. What if she needed that love for more than just herself?

After Nightmare Moon's defeat at the hooves of Celestia, the changelings fled Equestria to find new sources of love. As they went centuries without making any real trouble, the mortal inhabitants of Equestria came to think of them as just legends, and Celestia thought that they were not a threat without Nightmare Moon/Luna to lead them, or even that they had gone extinct. After a millennium of fending for themselves, changeling society and possible even biology changed enough to account for any unfamiliarity Celestia may have had with them.

Possible reasons for why they didn't rejoin Luna-

• After a thousand years, the changelings no longer remembered that they once served her.
• A feeling of betrayal and abandonment after the Nightmare Moon incident.
  • If Luna and Celestia thought that the changelings had died out, than Luna might not have tried to find them.
• The Queen preferred working for herself.

Changelings are the reason that alicorns are so rare.

Long ago, the alicorns were once as numerous as the pegasi, unicorns and earth ponies. One fateful day an alicorn mare had fallen in love with a stallion who was already taken. Using her powerful magic, she secretly kidnapped the other mare and used her magic to assume her form, fueling the spell with the stallion's love for her. The wickedness in her heart corrupted her true alicorn form into the first changeling queen. The kidnapped mare, now drained of all love in her heart, became the first changeling soldier, and the stallion she had deceived became the first changeling drone. Forever stuck as twisted perversions of ponies, the changelings used their powers to assume the forms of other alicorn couples, draining them of their love and turning them into more changeling soldiers. As their numbers grew, they quickly evolved to create cocoons for storing their "food" and future changelings in. In very little time, most of the alicorn population had been transformed into changelings, but only those who weren't of royalty- the changeling queen of the time figured that royal alicorns, such as Princess Celestia, were too risky to attempt assimilation upon, and so they went into hiding to wait for a golden opportunity to strike.

The Changelings were the results of the Shivans, the Forerunners, the Reapers, or even the Protheans experimenting on Ponies.

It would make a lot of sense.

Changelings are corrupted Alicorns.

Once, before Celestia's and Luna's rule, the Alicorns were a plentiful type of pony, similar to unicorns, pegasi, and earth ponies, but they were extremely scornful of the other ponies, thinking the Alicorns were much better than all the others. They loved to make life a living hell for the lesser ponies, even going as far as to learn shapeshifting spells that relied on love to cause chaos within the pony tribes. They eventually found they enjoyed the shapeshifting spell. They did this borderline every time, slowly turning them mindless and mutated. Eventually, all they knew was how to fly, and shapeshifting. They multiplied and caused total chaos within the pony tribes. Celestia and Luna, on the other hand, despite growing up among these monsters, chose not to act like the others of their kind, and instead, fought them. After a long battle, they eventually ran them out of what would eventually be Equestria, calling them Changelings. The Changelings, unable to return (for now), became nomadic, waiting for the chance to return and cause chaos for the lesser ponies.And as for Chrysalis, she was a strong, smart Changeling who was aware of her Alicorn roots. She learned other spells other than shapeshifting, so she could take over the areas the Changelings found. She was crowned queen for her intellect and power.

Changelings are the result of the story from "Hearts and Hooves Day".

There has to be some connection. An entire kingdom destroyed by love. Plus the princess in the book is depicted as an alicorn.

The Changelings are descendants of a Zerg brood that got stranded on Equestria millennia ago

The abundant magic that permeates the planet somehow partially severed them from the Overmind's control, and also affected their divergent evolution, taking them further and further physically from the baseline Swarm. Queen Chrysalis is essentially their Kerrigan: a former native-species member captured and Zergified. Like Kerrigan before her purification at the end of Wings of Liberty, Chrysalis is unconsciously operating under the psychic/genetic commands of the Dark Voice, with the ultimate goals of creating Hybrids of pony and Changeling/Zerg, and of weakening the planet's ability to defend itself when the Dark Voice eventually arrives in the material realm.

Changelings are NOT undead monsters.

This supposed origin story — put in the mouth of Chrysalis, no less — is just anti-changeling propaganda by some pony supremacist group, mistakenly published as a fact by IDW.

Abilities and Feeding

Changelings can feed on familial and platonic love, not just romantic love.

Queen Chrysalis was able to defeat Princess Celestia because she was drawing power not only from Shining Armor's love for his fiancée, but also from Princess Celestia's love for her niece.

• Implied since when confronted with the mane six, they turned into copies of them.
  • Wasn't that just so they wouldn't know who was who?

The Changelings take on the basic shape of the most dominant life-form when visiting new worlds.

They looked like ponies in this case, but had they visited the human world, they would look more human-like.

The Changelings come in millions of varieties, all able to copy the appearance of what it looks like.

That is, there are the basic pony-Changelings, then griffon-Changelings, dragon-Changelings, Changelings for most species of animal, etc. Their eventual goal is to replace every living thing on Earth.

Magic fueled by The Power of Love and The Power of Friendship can't be consumed by Changelings.

As shown in the end, they were effected by the Heart Beat-Down Cadence and Shining Armor laid on them. When channeled into a magical weapon like the Elements and the attack that defeated them, it's changed in such a way that they can no longer absorb it. Think of it like a human and water. Humans can drink fresh water and must do so to survive, but drinking salt water is detrimental to our health. Magic fueled by Love is essentially the same thing to Changelings.

• I figured they can only consume love that they intercept by shapechanging into the proper recipient.
• I argue that it would like trying to drink from riot control water cannon as it's blasting you in the face.

Changelings feed on the magic of love, not the emotion.

Consider: Friendship, and by extension love, is magic, right? Well...that means that friends and lovers regularly (and for the most part probably unconsciously, simply by reflex) exchange actual magical energy with each other, and it's likely this exchange that justifies The Power of Friendship and/or Love in the setting. Enter the Changelings, who can metabolize exactly this form of magic (but not automatically others, which explains why Shining Armor's shield and Twilight's magical bolts affected them normally) by intercepting the 'friendship beam' without giving anything back in return and quite likely even have the ability to tease more power out of a suitable 'donor' than they would normally readily send out on their own...

Changelings can turn ponies into more changelings.

Drain somepony of all their love, and they become another loveless monstrosity. Because it would be cool if it worked that way.

• Or the process of changing pony into changeling is similar to how vampires bite their victims - the changeling inflicts as much venom into body of their victim until its indubitable that the bited pony will soon transform into one of them. Or they use spells unique to their species in order to convert ponies into changelings. Or they produce special kind of their slime that has power to changelingifie ponies. Or their cocoons are not only used to store their prey, but also to metamorphize ponies into changelings. The possibilities about how changelings turn ponies into more changelings are limitless.

Ponies that have been drained too much turn into Zombies.

Sorry Spike, zombie ponies are looking more and more likely. Better find a shotgun or work on your fire breath.

Changelings can only impersonate living ponies.

Chrysalis left Cadence alive only because she needed her alive in order to adopt her form — otherwise, it would be a pretty silly move. She also left Twilight alive, so that a changeling could copy her and hence insert itself into Celestia's trusted circle.

Changelings can only feed off the love of living beings.

The magic of love needs to be a mutual bond, not an one way love of one being has to a deceased one. They can put mind control spells and bend the rules, but they cannot create fake love or love of the dead. That is why the Changeling queen allowed the let the princess to live.

Changelings don't really look anything like ponies.

Their basic form is an amorphous mass of black rotten flesh. However, each time they attack a race they shape their bodies into a basic likeness of that race, because having the basic frame ready makes imitation of specific members of the race faster and easier. That means, had they attacked Earth, changelings would have looked like black insect-winged human zombies.

The longer a changeling has been successfully impersonating somepony else, the harder it becomes to break the facade.

The swarm that were fought by and impersonated the Mane Six were very easily unmasked, being taken out by being KO'd. However, they were only in that form for a few minutes, tops. Chrysalis, on the other hand, was only unmasked after she revealed herself of her own free will, and it can be assumed that she was impersonating Cadance for quite awhile, possibly a few months. The longer she went without being revealed, the stronger her facade became. Plus, if the duplicate background ponies are changelings, this explains why they've never been unmasked. They've been impersonating somepony else for a long time, for several months. Maybe even years.

• So they become the mask?
  • Well, they don't seem to be all that bright (except for Chrysalis — she is queen, after all). If someone slow-witted as them were pretending to be somepony else for a few years, they might forget that they're not really them. Some of them probably wouldn't want to go back, even if they did know the truth.

Changelings have a weakness to apples.

The trading card of Queen Chrysalis warns that someone who rejects Applejack's treats is probable a changeling. Not food in general, but food made by Applejack. Since she puts apples in everything, this implies that the problem is the apples, so they might just have an allergy, or apples might even strip them of their powers.

• Specifically food made by Applejack? Hm...then there may be an alternate explanation unrelated to apples as such. Element of Honesty, remember?
• Changeling allergic to apple juice. Old Mare's Tale? Or new superweapon in the fight for Equinity!?

Changelings project an aura which reduces the intelligence of any sapient species within a wide radius.

This effect is meant to make their shoddy attempts at impersonation harder to see through. Sadly, Changelings are not immune to their own ability, which is why Queen Chrysalis' plan in A Canterlot Wedding was dumber than a box of rocks. (Bridesmaid guards? Seriously?)

This is the only way to explain why, whenever Changelings are involved, everybody seems to become stupid. The Queen did not put any effort into impersonating Cadence, and yet she fooled everyone but Twilight. In the IDW comics, changelings manage to temporarily break the Mane Six' friendship, and keep in mind that at this point the Mane Six were already fully aware that the changelings had returned. Even Twilight fell for it, this time. You can't explain that.

Hate has a deadly effect on Changelings.

Given how they feed off of love, it would make sense that feeding on its polar opposite would have detrimental effects on Changelings. Hate would severely weaken them, cause them horrible amounts of pain, and even kill them.

Changeling biology.

• The holes in the changeling's fetlocks are spiracles. Long story short, they breathe through them.
• Their mouthparts are more complex◊ than first glance would suggest.
• They're carnivorous as well as Emotion Eaters. Love energy is simply a dietary requirement, like vitamins. They can eat directly but prefer to cocoon their prey in pods full of digestive juices, like spiders.
• They produce a substance in their abdomens that can be chewed to make it pliable, and it sets into an organic plastic once exposed to air. Basically, beeswax or resin.

In the long term, Changeling feeding is fatal to their victims

Which is why, in "To Change a Changeling", it's noted that plants have begun to grow around the hive again now that the Changelings have stopped sucking the love out of everything around them. Under Chrysalis, Changeling magic was an inherently parasitic thing and harmful to those around them: either they drained their victims' vitality as they consumed their love, or they moved on to it to sate their hunger once all the love was used up. As such, it was impossible for anything to live long-term around their hive: eventually, the ever-hungry Changelings killed off everything around them to sate their hunger.

Other Guesses

The Changelings have a translation error.

When they say "love" they mean "blood". So they feed on blood. That's what the fangs are for.

• One day, the Changeling Queen heard the word "love" from a pony and asked what it meant. The reply was some poppycock about "it makes you feel all warm inside", "you need it to live", and "it comes from the heart", which she took the wrong way.
• It does make quite a bit of sense. Maybe the changeling word for 'blood' sounds and/or is spelled the same as the pony word for 'love'.

Changelings have been around for the entire series.

They've just been mimicking normal ponies the entire time, and done nothing to draw attention to themselves. Any of the background ponies could be changelings.

• Holy mother of Celestia.
• It gets better. You know all those duplicate assets Studio B uses for crowd shots? So they can fill out a scene with identical ponies to save time? Are those supposed to be there?
• Better yet. Now we know why Bon Bon's voice is different every time. Each appearance is a different Changeling taking her form.
• I'm Lyra Heartstrings, yes I'm the real Heartstrings, all the other Lyra's are changelings imitating, so will the real Lyra Heartstrings please stand up, please stand up, please stand up?
• The Jerkass ponies in "Putting Your Hoof Down" may have been Changelings all along!
• There is no proof that mook changelings can also mimic voices
  • When Twilight Sparkle said "They're Changelings, remember?" just before the brawl with the Changelings, many of the Changelings taking Twilight's form repeated the phrase in her voice.
• Underped Derpy.

Everypony is a Changeling.

But some of them have become the mask.

Crashing the Wedding was the changelings' plan, but it wasn't just for a quick nip.

Consider the following; The Changelings have been planning this for a damn long time, scouts have been taking quick nips at Equestria here and there, but not enough for the entire race. So the Queen makes an executive call and they start to put a plan together. Princess Cadence is planning a high profile wedding with Shining Armor, captain of the guard, so they abduct her, and use their love for each other to stage a massive invasion, with the Queen being placed on the inside as Cadance and the shapeshifter troops gathering. But it wasn't enough just to screw around and feed off the chaos of the attack, when they can best feed off sustainable emotions of the strongest variety. No, they were after something, and Celestia led them right to it when she told the manes to get the Elements of Harmony. Celestia either broke the spell she had on them after Discord bypassed it, or allowed access to the 6 of them if they were indisposed, but if the Changelings could mimic the 6 and get to Canterlot Tower before the manes could blaze a trail, they would get first crack at the most powerful magic known to Ponydom, and the ultimate tool of serenity. You give emotion eaters that sort of power, and they could very well never go hungry again. Granted it may cause the Third Impact, but hay, at least everypony is happy, right?

A changeling will become a new Mare-Do-Well.

She'll be under the impression that the original was another changeling herself. Bonus points if she outs herself as a changeling and starts calling herself the Martian Marehunter.

For most of the series, the Changelings were trapped in Tartaros.

But then Cerberus ran away in "It's About Time"...just long enough for at least one swarm to slip out. Nobody noticed their escape at the time because (a) there are no guards in Tartaros itself (the inmates are too dangerous), (b) they're shapeshifters, and (c) they didn't go on a rampage straight away the way some other escapees might have, so when they suddenly attacked Canterlot they came out of the left field for everypony.

• No, it was Tirek.

Changelings are either symbiotic or parasites.

Those cheese legs are not just for show. They look awfully like moth-eaten clothing, don't they? Changelings are infested with a species of worms, perhaps granting them their shapeshifting powers as a symbiotic tradeoff. Maybe the worms eat their flesh and Changelings depend on eating love to regenerate, or maybe the worms themselves feed on love... but perhaps can resort to eating flesh if left unfed for too long...

A good Changeling will eventually join the mane cast.

The episode that introduces him/her will play out like Zecora's introduction episode but the Aesop will not be "don't judge the appearance" but instead it will be "don't judge someone based off of what others do."

• And he will be named William.
• Confirmed, mostly. A good changeling — namely Thorax — did eventually show up, and his debut episode's moral did focus on not judging someone by their appearance. He did not become a part of the main cast, but he did become a fairly important supporting character.

The last race targeted by the changelings were humans.

Cadence!Chrysalis compared Pinkie Pie's decoration of the reception to that of a "six year old's birthday party" although horses are adults at six, and this seems to be true for Equestrian ponies (Pipsqueak being under a year old, the Cake twins running, flying and doing magic within a month). Now what kind of animal is still a juvenile at that age?

• An animal that ages like human, like the most members of the cast.

Now that the changelings have been driven out of Equestria, we won't see any more duplicate background ponies.

Or maybe not. Perhaps not ALL changelings were driven out of Equestria, only Chrysalis' invading swarm.

Chrysalis' Kingdom was starving by the time they arrived in Equestria.

This explains why the Queen's plan was a bit rushed. Her swarm had already failed to conquer several countries, and was dying of hunger. The invasion was a desperation move to stop the Changelings from dying out. She had to go for the largest city - Canterlot - to find enough prey to feed the whole swarm, but she had very limited time. That's why she didn't take the time to learn Cadence's personality better and instead relied on brute brainwashing to keep Shining Armor under control. And yes - that means all the changelings have died of hunger after they were expelled from Equestria.

Parasprites are changeling larvae

Unlike all other species, the changelings/parasprites age out of sexual maturity. The larval stage is the only time that they eat real food, in order to grow and reproduce. After about a year as a parasprite and a metamorphosis, they turn into changelings, which they can exist as indefinitely, as long as they don't starve and aren't squashed. Technically, if you kill all the parasprites, the changelings will eventually die out, because they can no longer reproduce. But we all know how hard it is to get rid of parasprites...

• Also, the holes in their legs, wings and hair are caused by their little siblings getting a little too snacky.

The mirror pool clones are changelings.

When somepony clones their self, they are not making a clone but rather summoning a changeling. The summoned changeling uses this as an opportunity to feed off of love undetected. When Twilight destroyed the Pinkie clones, she did not kill them but rather sent them back to where they were summoned from.

• Jossed, they're their own species.

After the crashing of the Royal Wedding and the expulsion of Queen Chrysalis, Equestria and many of her allies have declared that an open state of war exists between them and the Changeling Swarm.

And they are going to stop at nothing until the Changelings accept the terms of unconditional surrender or are WIPED OFF THE PLANET ENTIRELY AND DRIVEN EXTINCT.

• Jossed. At the end of "To Where and Back Again", they were perfectly happy to make peace with the Changelings and let them live on their own terms, without asking for terms of surrender, after the Changelings rejected Chrysalis and turned good. And in all honesty, it wouldn't be terribly in character for the ponies to do otherwise.

The Changelings inability to understand love is a Restraining Bolt on the species.

If the Changeling could actually feel love, they could immediately replenish their strength. While this may neutralise them as a threat, somepony thought that they might still want to feed on others' love. After all, just because they love each other doesn't mean they'll love you enough to stop their assault. Plus with the love they can feel constantly replenished, you would have the Changeling invasion without any need for stamina. To prevent them becoming too much of a threat, somepony stripped them of their ability to feel love. Whether they were a major threat before or they screwed up royally is up for debate.

The Changelings would be willing to protect Equestria from outside threats. Not because they care, but because it's in their best interests.

They want Equestria because its status as a Sugar Bowl makes it a perfect target. If another villain successfully conquered Equestria, then the standard of living would go down and the Changelings would have less to feed on.

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