As soon as the two women entered the next chamber, they immediately noticed the overwhelming stench. Luna was forced to bring up a hand to cover her nose as her sister coughed uncomfortably beside her. The entire room was filled with a heavy, fetid musk that seemed to come from everywhere, but it wasn’t until the two of them proceeded further into the room that they were able to identify its source.

Two large pits were positioned on either side of the cavern, each filled with its own, overwhelming portion of brown muck. Luna could only guess what it was, but she was pretty sure she’d be right.

“Mmmmm, breathe it in, girls,” Chrysalis’s husky voice taunted from nowhere and everywhere at once. “Doesn’t that just smell wonderful?”

“You are a disgusting creature,” Celestia spat venomously. “What in Equestria could possibly be the purpose of this place.”

A chuckle echoed around them. “Oh, you mean the cesspits?” she inquired with thinly-veiled malice. “Well, all of my changeling’s need to shit somewhere, Princess. It wouldn’t be very sterile to just have them squeezing out their thick, stinky logs all over the hive, now would it?”

The admission confirmed Luna’s suspicions - the pits were filled with manure. “Of course it is,” she grumbled under her breath. What was with the changeling queen and her outright obsession with scat.

“More shit?” Celestia questioned, similar thoughts seemingly running through her mind. “Are you kidding me? Why?”

“Mmmm,” Chrysalis hummed for a moment, as if pretending to consider the question. There was no hope of a serious answer, however, as she continued. “Well I just suppose the thought of the two of you defiling yourselves gets me off. To you, Celestia, with that pristine white coat absolutely smothered with vile filth… unf! Talk about getting my rocks off!”

Luna’s eyes widened at such a blatant and lewd admission, and a blush tinted her cheeks as more of Chrysalis’s playful, exaggerated moans echoed around the room. Celestia, however, was livid at the remarks. “That will not happen,” she countered pointedly, and the queen’s moans devolved into a fit of cackling laughter.

“Oh my!” she managed to choke out. “So bold! So sure of herself! So oblivious to her current situation!” The laughter abruptly cut out, leaving a chilling moment of silence to linger in the dank, stinky air of the cavern before Chrysalis’s taunting voice returned. “There are steps on either side of the room. Climb up them and wait at the top.”

The two alicorns reluctantly went in opposite directions towards their separate stairs. They were steep, carved directly into the rock face of the wall. Luna almost lost her footing multiple times as she climbed to the top. She didn’t realize that she had been holding her breath until she reached her platform and took a deep, shuddering breath.

Celestia didn’t seem to have any trouble with her climb, reaching the top of her side with ease. She stared at Luna across the chasm between them, her emotions unreadable as Luna took her place standing directly opposite her.

The platform was a small, rocky precipice jutting out from the cavern wall, hovering ominously over the two pits of sewage. Beside it was a small, wooden circle with a target crudely painted on it. Looking across, Luna could see that Celestia’s platform had a similar target as well.

“This task is quite simple. All that you need to do is take those three stones beside you, and throw them at the target opposite you. If you hit it, the trap door beneath the other’s hooves will open, and they will fall into the warm pit of changeling shit below.” Chrysalis’s voice rose with glee as she reached the end of her explanation, unable to fully hide just how excited she was to see who it was that would fail this task. “Good luck!”

There was silence for a moment as both sisters simply stared at each other from their opposing perches. Luna glanced nervously down at her own collection of smooth, roughly spherical stones before her.

A sudden thunk next to her startled the woman out of her trance, and she looked up to see that her sister had already cast the first stone against her. It had missed, thankfully, but already Celestia was rearing back her arm to throw the next one.

“Sister!” Luna exclaimed in shock.

“What?” replied Celestia as she threw the second stone. Luna flinched as it collided with the rock face just short of the intended target. “You heard the challenge, same as I did. Might as well get to it.”

Luna gaped at her sister. “You can’t be serious,” she said indignantly. “But we… you are… you’re our sister!”

Celestia’s face darkened as Luna protested, but she hesitated in throwing the next stone. “Indeed, Luna,” she conceded quietly. “But I did not see that stop you in the last challenge.”

There was a heavy weight behind Celestia’s words, one that fed the growing regret in Luna’s heart. “We did not intend to harm you,” the younger alicorn said. “We tried to choose the best option.”

“There were no good options,” Celestia hissed. “The best option would have been not to play.”

Luna balked. “But you were the one who told us to just play along!” she retorted. “We were doing just that! Or was that only when we were on the receiving end and not you, sister?” Then because she was feeling petty, she added, “Besides, with the amount of analingus you probably perform, I bet that you would enjoy that cesspit!”

Celestia narrowed her eyes. “I don’t eat ass,” she said coldly and threw the last stone. It fell short, and fell into the pit of muck below with a disgusting splat. She let out a grunt of frustration as she realized she was out of stones.

Now riled up, Luna reached for her own set of stones. She lifted one up, gauging its weight in her palm as she eyes the target across the chamber. The younger alicorn had done this plenty of times at carnivals in her youth. She remembered her sister and her wandering around the fair aisles with bombastic, upbeat music blaring all around them as they enjoyed their time together. Now her sister stood across her with her arms crossed and a downright villainous glare pointed her way.

Luna hardened her gaze in response and took her stance to throw her first stone. She aimed carefully, pulling her skills from her memory, and raised her hand. Then, making sure she was aligned properly, she swung forward and let the stone fly.

Celestia’s eyes widened as she saw just how accurate Luna was. The first stone grazed the top of the target and ricocheted off into the cavern below. The second one hit just below it, causing a hollow, metal clang to ring out, but the target was otherwise unmoved. Just a little bit lower, however, and Celestia would be sent down into the stinky pit of changeling manure below.

Her eyes darted back over to her sister, wide and pleading for her next toss to miss. Luna met her gaze, cold and steely, as she raised her arm and cocked it back, ready to launch her last stone at the target.

“Do you remember those old carnival games, sister?” Luna asked suddenly. The even tone of her voice did nothing to calm the growing anxiety within Celestia. “The ones where we had to hit the target to win the prize?”

Celestia nodded in reply. “Yes,” she said quietly.

“We were always very good at those.”

That was the only warning that the alicorn got before her sister swung her arm and sent the last stone flying towards the target.

The stone impacted the center of the target dead-on. The metallic ring echoed out in the cavern as a sense of acute dread filled Celestia. She braced herself for the inevitable - squeezing her eyes shut and waiting for the floor beneath her to give out. Yet nothing happened.

She popped one eye open after a moment. She was still on the platform, and nothing had happened. A weak laugh escaped her lips - a sound of relieved mirth. But it was a mirth that was quickly killed by a raspy voice.

“Oh dear,” Chrysalis tutted out. “That is most unfortunate. It seems my little contraption malfunctioned.” Celestia let out a sigh of relief. Perhaps she could avoid this horrible punishment after all- “I’ll just have to manually fix that, hm?”

Celestia panicked as she felt the tell-tale tingle of another pony’s magic grab hold of her. She flailed her arms wildly as she popped out of existence for a moment before reappearing right below her rocky platform. The brown muck of the pit suddenly rushed up to meet her as gravity took hold, and the princess let out a scream of fear as she fell towards it.

Somehow, despite sitting in the damp cave for however long it had, the pit of sewage was still warm. This provided absolutely no comfort to Celestia as she hit the mess with a disgustingly slick squelch. Her body sunk right in up to her breasts, coating most of her body in the changeling shit.

The alicorn simply sat there for a moment, motionless, as her body struggled to process the situation she was now in. It was absolutely disgusting, and though she had been revolted at the idea to start out with, it seemed as though Celestia just simply could not fathom how she had gotten to where she was now. The process was simple, a single line connected through the compounding series of events that led her to this moment, and yet, it was seemingly equally impossible that she was currently chest-deep in a pile of sewage.

Celestia fought back against the growing nausea in her chest. As foul as this experience was, she would not give Chrysalis, nor her sister, any sort of satisfaction in their victory. She raised her arms as high as she could above her head, and slowly tried to make her way towards the edge of the pit. The sludge was thick, and made it incredibly hard for her to move. Each shift of her body smeared more of the filth against her skin, absolutely covering her lower half in the fetid crap. It squished underneath her hooves as she trudged through it, and she grunted from the exertion of forcing her body through it.

From above, Luna had watched as Celestia had fallen. The sickening noise that she had made as her body slipped into the cesspit below churned her stomach, and she looked down to see the older woman half-buried in the mound of scat, not unlike a stick in a pit of mud. She watched as her sister fought back an obvious wave of disgust - calming herself down before she began to slowly inch her way forward in an attempt to get out of the vile filth she was in.

It took what felt like ages to reach the edge of the pit, with Celestia’s body getting only dirtier as it went. She could feel the vile mixture of semi-solid slop mixed in with the occasional, firmer log as the mixture pressed and smeared against her body. Disgust turned her stomach as each press of her hoof down into the mess smushed even more changeling feces against her skin, and she could somehow feel certain patches of shit that were warmer than the rest.

Then, her eyes widened in a combination of shock and horror as a small portal opened up just a few feet above the surface of the pit. There was a faint sputtering sound, followed by a thick log of rich, brown shit slowly descending out of it. It coiled down sloppily onto the rest of the cooling scat below, its lighter color standing out against the darker surface of the cesspit. It tapered off with a second fart, only to let a smaller rope of shit slither out right behind it.

As the second coil of fresh feces draped over the first, the portal abruptly closed, leaving no trace that it was ever there besides the additional manure that had been added to the already overwhelming volume of waste in the pit. Celestia swallowed thickly. Somehow, the idea that this was an active sewer for the changeling hive made her predicament somewhat better. Not that she was relieved by any means, but there was something less disgusting about this than the idea that she had been wading through month-old shit.

The smell of the new serving hit Celestia’s nose after a few moments, and she swallowed thickly as she continued to try and make her way out. She paused, only briefly as she passed it, staring down at it with a feeling of contempt. Its greasy, wrinkled surface stared back up at the alicorn, and she wondered how she ended up here. Her gaze shifted up to watch as Luna carefully made her way back down to the ground, and a feeling of anger gripped her chest as she resumed her journey out.

Celestia was hauling herself up and out of the cesspit just as Luna reached the bottom of her stairs. There was a disgusting, slippery sound as her sister yanked her foot free from the sludge, finally out of the cesspit entirely. She straightened up on shaky legs, grimacing as the cool air of the cavern quickly began to cool the scat caked to her skin. Looking up, she saw as her sister slowly approached her, and she took a few steps forward to meet her halfway - each step leaving behind a vile, brown footprint on the hard stone of the floor.

Luna couldn’t help but stare at Celestia as she approached. Her sister’s entire body below her tits was covered in a thick paste of deep, brown muck. It absolutely reeked, the scent of the agitated waste much stronger than the latent smell of shit in the room. She glared at Luna as the younger sister looked on in shock, the prior coldness in her demeanor replaced with a fiery anger that had nowhere to be directed except at the other alicorn.

“Don’t look at me like that,” she hissed. “What, are you jealous?”

Luna balked at the question. It had seemingly come out of nowhere. “Jealous? Why in the world would we be jealous, sister?” she asked, a small part of her fearing the answer she would receive.

In response, Celestia just let out a short bark of laughter. “Well, given the way you’ve been treating me like shit, I figured you would have wanted to bathe in it as well. It isn’t like you haven't grown accustomed to the taste, either,” she ranted angrily as she scraped a large chunk of scat off of her upper arm with disgust. The sludge clung to her fingers and Celestia looked at her hand with loathing for a moment before she flicked her wrist, flinging the changeling shit towards her sister.

The glob of filth hit the floor a few feet away from her with a sickly splat. Luna didn’t even bother trying to move out of the way - she probably deserved it anyways. Celestia flicked another, smaller piece of shit off of her soiled arm, but this time the glob arced through the air to land just above Luna’s mouth. The younger alicorn flinched as it hit her, and her mouth turned downward in disgust.

Celestia hadn’t meant to hit her sister in her face.It had been mostly an accident. Automatically, she reached out to wipe the offending piece of changeling scat away. She extended her thumb to wipe at Luna’s upper lip, but just as the other alicorn opened her mouth to brush Celestia’s actions away, her finger ended up going right in her sister’s mouth.

Luna’s lips closed instinctively around the intruder before she could fully realize what was happening. The horrendous, bitter taste of the shit coating Celestia’s thumb seeped into her mouth as her tongue unconsciously rose to meet it, and she nearly gagged. But she was too surprised to fully react, and simply just stood there, bearing the awful taste with shocked, widened eyes, staring back at her equally surprised sister.

For her part, Celestia also stood there, confused by what had just occurred. Her surprised expression slowly morphed into something more contemplative as she felt Luna’s tongue slide against the pad of her thumb. Slowly, she withdrew backwards, pulling her finger out of her sister’s mouth. But Luna’s lips did not part, and when Celestia’s tumb was pulled out, it was mostly clean of the significant, fecal residue that was on it prior.

The alabaster alicorn stared at her clean thumb in shock - only to be pulled out of her confusion by Luna suddenly gagging and spitting the disgusting scat out onto the floor at her feet. “Sister!” the smaller princess exclaimed. “W-what? Why would you do that?!”

Before Celestia could explain herself, Chrysalis’s voice came echoing out from nowhere again. “Now now, Celly,” she chastised menacingly. “Play nice. Don’t be a sore loser, otherwise…” she paused for just a moment, and both alicorns could hear the vile grin stretching across her face in the brief silence. “...I may have to mix in a few extra punishments in return.”

Celestia let out an indignant huff as she once again began to scrape more of the shit off of her body. She didn’t have time to ponder her sister’s actions right now. The stinky filth was drying against her skin and stiffening her gown - which was absolutely ruined after that ordeal - and was overall giving her one of the most unpleasant feelings she had ever suffered through. The best course of action would be to shed the gown entirely, but that would leave her completely exposed for whatever challenges may come next. The alicorn weighed the options in her mind before ultimately deciding to remove her clothing.

“Fuck it,” she muttered as she took the ruined fabric in her hands and simply tore it away. Luna started at the sudden curse, not used to such language from her sister. She was even more shocked at just how roughly Celestia ripped her gown off and threw it to the floor, leaving her completely nude.

While the once-white dress had in fact been coated with a majority of the changeling shit, Celestia’s arms, legs, and hooves were still covered in a thick layer of brown. She tried her best to remove most of the offending sludge with her hands, leaving large clumps of shit on the floor around her as she did her best to clean herself off. Her fingers dragged through the thick manure, scraping it off of her skin in thick, stinky chunks. It was an ineffective method, leaving behind long, brown stains across the pale skin of her arms, staining the once impeccable alabaster with not only a crusty residue of scat, but the horrid scent of shit as well.

Luna watched from a few feet away as her sister did her best to clean herself off. She tried not to pay too much attention to the way Celestia’s body stretched and bent to access the harder-to-reach parts of her calves and hooves, unknowingly putting on some sort of perverse show for anyone who may be watching. The alicorn could not prevent a slight blush from filling her cheeks as Celestia fully bent over to wipe the shit from the bottom of her hooves, fully baring her ass to Luna. Her cheeks parted just enough to show off her pussy and asshole, and it seemed that both of her holes had seemingly been spared from having a large amount of scat smeared across it. Celestia’s wrinkled pucker, however, still gaped slightly from the rough treatment she had previously received, and Luna’s mind could not help but wander to how that must have felt.

And what was it that had just transpired? Luna couldn’t say she enjoyed the taste of her sister’s shit-coated finger in her mouth. It was no doubt some antagonistic payback for everything she had put her sister through to this point. But, that seemed like a step too far - even in retribution. Luna didn’t know what to make of it.

Before she had any more time to dwell on the sight her sister was giving her though, Celestia straightened back up with an aggravated sigh. It seemed that she had gotten all of the shit off of her body that she reasonably could. The taller woman turned to face her sister, and Luna noted with some small relief that her face no longer held the intensely hostile gaze it had just minutes prior. Instead, she leveled an annoyed stare at Luna, and put her hands on her hips.

“Are you done gawking,” she asked, cocking a hip to the side. “We should really get on to the next challenge.”

“We’re sorry,” Luna said, almost automatically at this point. “A-also, we weren’t gawking.” The addendum felt necessary, even if it was false.

“Mhm, right. Let’s just go,” Celestia said. She started walking before letting Luna respond. The newfound routine would help to clear her head. Regardless of what Luna’s reaction was to her accidental action earlier, there was no denying that Luna definitely deserved what had happened. Celestia did not care about her sister’s apology, nor whether or not she had in fact been getting an eyeful of her nude form as she scraped the filth from her flesh. This was a game - a series of challenges, as Chrysalis had described. Even if she was down by two now, the first challenge had proven that Luna was not infallible.

Her win would come.

Author's Note

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