Animorphs: The Symbiosis

by Avatar Sprite

First published

It started as such a nice day for Twilight. Becoming a Princess was something she never planned for, neither was becoming a Controller

Twilight knew of other sentient species on her own planet, Twilight knew of life in other dimensions, what Twilight didn't expect was there to be life from other planets. She especially didn't expect that life to be already invading Equestria.

Set straight after the ending of Season 3, Animorphs: The Symbiosis is an MLP / Animorph crossover that won't, at first anyway, feature the Animorphs at all. Instead, it focuses on the Yeerks, and the interplay between the Peace movement, and the rest of the empire.

The Begining: Chapter 1

View Online

My name is Twilight Sparkle, Princess Celestia’s favored student, Princess of Friendship, and as of last week, Pony-Controller. If that term confuses you, then congratulations, probably! You are obviously unaware of the war going on. This isn’t an ordinary war, with Warrior-casters, and Pegasi shock troops. No, this is a war so insidious even some of its own combatants are disgusted with their ‘side’. This war is against the Yeerks, a parasitic species that at first glance looks similar to the common gastropod found in Equestria. This alien species, however, rather than being the bane of gardeners, is the bane of sentient species throughout the galaxy, you see they use their boneless body to slip into a pony’s body, through as yet undetermined means, and wrap themselves around the brain, sinking their hooks into every nook and cranny. Once they have done that, the Yeerk wrests control from the pony, leaving them trapped inside their own mind, as they watch the Yeerk move their body around, tricking everypony around them into thinking they are still them, as they work towards the conquest of ponykind behind the scenes.

The day I became aware of this war, was the day after my coronation. It was a grand affair, with banner-mares, and parades. I was tired out from the whole thing. On the train home to Ponyville, I had the girls with me of course, Pinkie Pie, Rainbow Dash, Rarity, Applejack, and Fluttershy. Some of the best ponies anypony could ask for as friends, usually anyway. The excitement of the whole coronation had everypony a bit frazzled.

“WOooooo Twilight!“ A pink voice interrupted my thoughts as I stared out the window, causing my new wings to spread startled as I tried to reign my heart back into my chest. “What sort of cupcakes do you want for your welcome to being a Princess party in Ponyville? I mean I know what old unicorn Twilight would have wanted. But then I thought to myself Pinkie, my old pal Twilight has changed from a unicorn to a Princess, that’s got to mess with the taste buds some.“

“I don’t know Pinkie,“ I replied with a tired smile. “I suppose I would still like chocolate ones?”

Pinkie’s response was a gentle gasp of realization. “Oooorrr I could make every flavor, then you could find out which one is your new Alicorn favorite flavor! Do Alicorns like chocolate? Or do they only like fancy flavors like Prench Vanilla? I got to go plan this.” Rushing off to the other end of the train car Pinkie left me alone finally to my thoughts. Of course, that didn't last long, as soon Rarity was sidling up to me.

“Princess Twilight, you simply must let me design a dress for you to wear. Wings and a horn will be a challenge to accessorize I admit, but never let it be said Rarity doesn’t appreciate a challenge”. Rarity said, horn already alight as it carried over a tape measure. “First let us see if your measurements have changed.”

“Rarity, it’s just Twilight,“ I sighed. “As I said the last five times.” Taking the tape measure in my own magic I put it back in her saddle-bags. “Can this wait until we get back home to Ponyville? I feel kind of awkward in the middle of the carriage like this.”

“Oh of course, and I am sorry Darling, you know it’s just so exciting, one of my friends, a Princess. I just can’t wait to get started, you must come to the boutique as soon as we get off the train.” Rarity smiled eagerly, closing her saddlebags back up. “We can get your measurements then have some tea. I got a new Saddle Arabian blend that Fluttershy said was divine.”

“Sure Rarity. Though how much measurements does adding wings need?” I yawned softly, settling onto the bench again. “I don’t feel any bigger, there’s no need for much.”

“Darling, your body type is totally different now. And you are obviously a couple of inches taller at least. And as for no need for much, the last dress was much too plain, nowhere near enough for a Princess.” Rarity looked scandalized at the very thought of me wearing that dress. I thought that that dress was one of the fanciest ones that ever looked good on me, inaccuracies and all.

“I suppose so,“ I smiled weakly, it was always best to go with Rarity when she got, as she called it, in the zone. “It won’t be too long right? I feel like I could sleep a week.” I spotted Rainbow snoring away on another bench. “Looks like Rainbow already started.”

“I shan’t take but a moment of your time Twilight.” Rarity replied, following my gaze for a second, she then looked back to me. “I believe so, Honestly, that mare could sleep through a hurricane”. The train jerked softly under our hooves shortly after that, Rainbow indeed remaining snoring loudly as the train came to a halt. Looking outside at the gently lit station, I soon recognized it as Ponyville station. Rarity moved off to try and wake Rainbow, as I collected my new baggage. “Don’t forget Twilight. Tea, and measurements at the Boutique.”

“I won’t, Rarity,“ I yawned again, longer this time as I moved to head towards the train exit. “You sure it can’t wait until tomorrow? I just want to get back to the library and sleep.”
A worried look flashed over Rarity’s face for just a second, just a minor twitch of, almost annoyance with it. Rarity’s expression soon smoothed though, replaced with her usual charming demeanor.

Collecting her own baggage, Spike not being around to offer his help, Rarity smiled slightly. “I’m sorry, darling. I just wish to get started on this right away, while the memory of your wonderful coronation stays fresh.”

At that, I could only shake my head and smile. “Don’t worry. I will be there, Rarity.” After assuring her of my attendance, and helping her with her bags off the train, I quickly proceeded home to the library. The first thing that greeted me when I came in was the still remaining scent of smoke and a large patch of soot on the floor. The other thing was the trail of gem dust from the kitchen to the stairs, and the snoring of a tired baby Dragon. Putting my luggage to the side, I briefly entertained the thought of joining Spike in slumber. However, Rarity obviously felt that this measuring was needed and I wasn’t about to let a friend down, so closing the door behind me, I left for the boutique.

As I headed over, I puzzled a bit over why this was so important to my friend. Yes, Rarity could get caught up in the flow of inspiration, and get a bit pushy about her craft. But to demand a soon to be late-night dress-fitting session was new for her. It isn’t like there is a deadline for creating a dress for a princess after all, though I supposed there can be some prestige in making the first one, I wondered if Rarity could be trying to make sure I don’t get accosted by dressmaking ninja’s to give me the first dress as a Princess? Chuckling, and deciding I should let Spike’s comic book plots stay in his comic books, I arrived at the Boutique, only to pause before knocking, finding the whole place darkened, lights off in every window apart from the back work-room. Knocking on the door, I decided to give it only a couple of minutes, after a long journey, I wouldn't have been surprised if Rarity ended up falling asleep as soon as she arrived home and if so I would want to be soon asleep myself rather than waiting out in the middle of the night.

“Come on in Twilight!” Came Rarity’s voice from inside the Boutique, tired, but awake. Walking into the Boutique, the door shutting behind me, I looked around with a yawn, spotting the door dimly lit with the glow of the light from the other side. Stepping forwards towards it in the dim light, I winced as I came nose to nose with a ponyquinn straight away. Using a light spell to provide a dim light I managed to navigate through ponyquin’s, dress stands, and clothes racks and finally arrive at Rarity’s work-room. My eyes acclimatizing enough to see through the maze in the dim light, I opened the door and spotted Rarity through the glare of the brightened light, and smiled, stepping through, shielding my eyes as they got used to the light again, I had but one second of warning, as Rarity nodded to somepony behind the door, and then a sudden weight from both sides assaulted me, The sharp sting of a needle pressed into my neck, as a ring slid down my horn. Another pony wrapped around my barrel, stopping my wings from opening. I looked confused up at Rarity as my vision began to swim looking at her, almost apologetic face as it faded to black.

The Begining: Chapter 2

View Online

The first thing I felt as I woke was just disbelief. There was no way Rarity just stood and watched as somepony assaulted me, no, no way she actually signaled to them to start the assault. The second thing I felt, was the straps around my barrel holding me into some sort of bench, holding my wings together. Opening my eyes I found nothing but darkness awaiting me. Taking further stock I felt a soft, almost silken fabric on my face, soft enough that the blindfold was almost unnoticeable apart from the light it blocked. A pressure on my horn told me they likely had a magic blocker on my horn, but while useful for standard unicorns, they were often unable to hold back longer amounts of high magic usage. As I started to attempt to channel magic, forcing through the rapidly forming headache, the bench I was on suddenly spun round as if on a gyroscope, swinging me around randomly, disrupting my concentration and almost making me sick in the process.

“I am so sorry darling” came a chillingly familiar voice, “We were hoping you would still be asleep for this unpleasantness”. Rarity sounded genuinely upset, but then, she was free, walking around me, while I was bound. Or at least she sounded like Rarity.

“Queen Chrysalis, Couldn’t get my brother or the Princess so after me now?” I spat glaring at where her voice last came from. “My friends will realize Rarity and I are missing, they won’t fall for your changelings this time!” I hoped anyway, a small part of me reminding me they didn’t believe me at the wedding last time this bug was involved.

“We aren’t changelings Twilight, far from it, this is Rarity, just … not only Rarity” Came the response, from yet another direction. “You will understand soon enough, and I can’t tell you how sorry this makes us believe me, darling, if we had any choice we would have, but we can’t risk them going through with their original plan tomorrow.”

“What do you mean not only Rarity, and what original plan?” I asked more confused than ever, as the bench I was shifted, pulled to the side of the room with a distinctive blue, not green, glow. “Who is they? If that is you, you don’t have to do this Rarity, whatever it is, I’m your friend, we can talk through this” As I finished talking, I tried once again to force power through the block, only to get spun once again.

“You will find out in a minute, Twilight” Rarity replied as she twisted the board so I was lying on my back and pulled it onto something. “I just hope you will be able to forgive us, eventually” Struggling against the bonds I tried to look at what Rarity was pulling me onto, only for part of it to lower down and dunk my head under some, for lack of a better term, sludge.

My struggling increased as my head was submerged my new wings pushing instinctively at the bonds holding them down as I struggled to hold my breath and close my eyes, assuming this was some new changeling cocooning technique. I was so busy trying to focus on not swallowing and holding my breath I almost didn’t notice the movement at my ear, a light tickle of something brushing against it causing it to flick out only to encounter resistance as some mass pushed back and deeper into my ear.

The pain was the most noticeable thing next, a sharp sting radiating into my skull that just as rapidly as it came dissipated into a numb ache. After a couple of seconds, I was pulled out of the water and Rarity looked down at me. “Please treat her carefully Yilo, Rarity and I count her as a dear friend.”

I don’t think I have ever been as scared as I was then, I could still feel this dull ache emanating through my head as this … monster was boring its way into my skull, and this fake Rarity just stood over me, gloating. I tried to look up at Rarity, to open my mouth to ask her why, but nothing happened, my own body refused to act on what I wanted. This is it, I thought, The monster must be eating my brain now, first motor control, soon everything else.

<Please, Twilight, Do not be alarmed.> The thought was suddenly there in my head clear as day, I knew I didn’t think the sentence, yet it was there. <I am not eating you, you are safe. I am Yilo 9856, now if you excuse me, I need to make sure Rarity and Yeion know it went alright.> As I ‘heard’ this, I looked up to Rarity, except it wasn’t me doing it, this .. Thing was not only thinking into me, it could use my body too, I tried my hardest to move away but nothing I did registered. “I do not plan on mistreating my host.” ‘I’ said, sounding almost, offended. “I may not have planned to take a host, but it doesn’t mean I won’t do my best. ”.

<What do you mean mistreat me? > I tried directing a thought at the creature, trying to distract myself from hearing my voice without my input. <I think invading my skull would most definitely qualify in my book.> To my surprise, there was a distinct sense that my thought was heard.

<Some Yeerks, will mistreat their host, torture them, break them. To me, and other members of our group, that is barbaric. Something that shouldn’t be tolerated, let alone applauded as it currently is> The creature, Yilo, replied with a distinct note of disdain. <Just because I require the use of your body, doesn’t mean I have to make it any harder on you than necessary>

As we spoke, Rarity’s horn glowed, and the restraints one by one were released. I couldn’t help letting several questions bubble through my head <You require my body? Wait, does this mean there is one of your things in Rarity too? > I think in pure relief, My friend hadn’t betrayed me! She was stuck like I am … On second thought, that relief was premature.

<I am hardly a thing> came back a tone of thought that had an almost audible sniff at the end of it. <And yes, Rarity is, as is our oxymoron of a term, a Pony-Controller. However, while indeed she has not betrayed you, she is a voluntary host>

<What do you mean, voluntary? Rarity would never do a thing like that.> I replied. <She wouldn’t betray her friends to you creatures.> Yilo moved me off the bench carefully. As disturbing as this was, I couldn’t help but let my mind race with thoughts on how this could happen, what kind of species would evolve to control a pony’s body like this?


<We didn’t evolve to control ponies, Twilight. We can control most creatures with a big enough cranial capacity.> Those words from the weird parasite sent my head into a spin, a multi-species parasite was always a rare thing.


<You mean like Saddle Arabians? Or more different species, like Griffons> I responded, Not even bothering to count the dragons, everypony knows they are not vulnerable to the same class parasite as ponies. The response to this seemed, delayed for a moment, I could have sworn I felt a strong feeling of, indecision, and almost guilt come from that spot of my mind the voice of this .. yeerk, came from.

Before he could answer, Rarity, or the thing in her, nudged me. “Come on you two, you can get to know each other on your own time, for now, I need to do a rush job, as it were, on measuring your changes before you return home.” She said, bringing out her measuring tape. “This won’t take long darling, just stand still” Rarity with this, started measuring in her usual whirlwind of pace when the subject comes to fashion. “I do wish I actually had all this time to measure you, your measurements have definitely been thrown off by those wonderful wings of yours.” She said, noting down the measurements as they come “Why you are almost a full centimeter taller! This changes all your dresses, you simply must let me redesign your dresses for this”

“Of course Rarity, and how much will it cost this time?” My voice replied. At this I couldn’t help but mentally grin at the obvious mistake, thinking that, Yilo hasn’t studied me or my friends well enough to play my role.

“Come now Yilo, If you are going to try and act in character, as it were, at least wait until you have had chance to fully get to know Twilight, the very thought of her asking how much I would charge her for this, it’s insulting!” Rarity chided, with a soft humph and upturned nose. “You two need to get home and get to work, I am sure Twilight has lots of questions to ask, and you have a lot to learn “ Rarity started ushering me, and Yilo I suppose, to the basement door “And I have a lot of work to do on starting your first new dress” she says opening the door. “Do come back tomorrow for more complicated measurements Darling”

<Rarity really would do your dress for free?> Yilo asked as we walked back to the library. <I know they are known as the Element of Generosity, but still.>

My resolve to not answer any of his questions rapidly crumbled at the last words there. <Rarity, Rarity is the Element of Generosity, not the parasite you have controlling her. You things don’t know the meaning of the term.>

A soft feeling of exasperation and, something that felt like but couldn’t be sympathy, came from Yilo’s corner of my head. <Twilight, Rarity has been partnered with Yeion since before you met her. I don’t understand magic, none of us do quite yet, but it still counts her as generous, even with Yeion’s involvement.>

Shock at that answer filled me. <Since the beginning? But she … > I fell to silence, unable to comprehend how long my friend, was one of these things.

<Please don’t worry Twilight,> Yilo thought, in a comforting manner. <You do know Rarity, unlike the main Empire’s feeling on things, our particular group believes in sharing control, not taking it. Not only have you likely spoken to Rarity, not Yeion quite a few times, it is them together as a partnership, that is the pony you became friends with.>

<I certinately feel shared with> I grumble. <I just love how you asked me to share with you>

<We regret having to take action like this Twilight, it was this or watching as someone less interested in coexistence, and good treatment was ‘chosen’ to infest you. As it were, we burned several assets to make sure I was chosen for this>

Getting through the door to the Library, Yilo paused for a minute, a soft sense of hesitation coming from him. <Would, Would you like to be in control to get yourself to bed? I can’t offer this all the time, and not when around other yeerks not in the movement, but, if you work with me, I can use a lot less harsh control, and we can get to know each other better?>

At this, I almost nodded before thinking, but stopping myself, I instead asked <Why should I be helping you? >

Yilo sighed. <I suppose without context, you don’t know. Tonight I will get myself aquatinted with your life, then tomorrow is the first time meeting with the non-movement yeerks, I hope after meeting them you can see who the actual villains are in this, and may be willing to work with me more.> He hesitated, <I just, Please know, what you see tomorrow? It’s why the movement exists, it is what we want to stop in favor of coexistence>