So I didn't intend to continue writing for "Undertale," but you know how things work. You get hit by inspiration and a cool idea takes root in your brain…

Well, anyway, this has no connection to my earlier story (though I am working on a prequel for this one). It was inspired by the visuals and such from an "Undertale" animation called "Echo" by v0idless (which can be easily located on Youtube). It is a very intriguing (and sometimes confusing) video that I highly recommend watching. The person who created it is very talented.

As I said, the visuals of the animation sparked off an idea. And the idea grew. And eventually this started to take shape and I started writing. Hopefully you'll enjoy it.

Just in case you're curious, I'm not Toby Fox. Which means I do not own "Undertale" or anything connected to the game. I am also not v0idless, which means I don't have anything to do with the animation "Echo." I'm just the crazy person who keeps losing any self-restraint and keeps writing a lot of stories.

So I hope you enjoy. My brain certainly has a good time coming up with these ideas.

Souls Shining In The Dark

How long he'd been trapped in darkness was impossible to judge properly. It could be eons of solitude as the Void tore at his mind with sights, sounds, and knowledge of every location and moment simultaneously. Or he could have fallen just a moment before, certain he would die and only beginning to realize this was far worse.

Have to get out. Have to get out. Have to get out.

His body was scattered, ripped apart and spread throughout the infinite darkness. His mind was frayed and unraveling under the constant onslaught. The fragments of his self were merged with the strange dimension. He couldn't hold on to his memories anymore. He didn't truly exist anymore. He could barely remember his own name.

Too much. Got to escape. Too much. Got to escape. Too much. Can't take any more. Got to escape.

He wasn't really a monster anymore, torn and scattered by his fall into his creation. He was part of the darkness. He was the Void now. But he hated how it continuously assaulted him.

Distance was as flexible and relative as time in the Void. Sometimes he could pull together a body in the emptiness, just like he could occasionally drag up a bright memory to flicker to life in the darkness before it quickly vanished again. But it wasn't enough. It didn't help.

Make it stop. Make it stop. Make it stop.

His sanity wavered in and out of focus, filling his thoughts with static and chaos. It hurt. Physical and mental pain remained an inescapable constant. Monsters were not meant for the Void and everything about the hostile environment made it clear.

He tried to claw his way out, seeking weak spots in reality to return. But even when he managed a few brief moments of real light and sound rather than the chaos ripping at his mind, he quickly snapped back into the infinite darkness of the Void. He was too broken. He couldn't pull himself together enough and he couldn't pull his body free. He couldn't escape. He remained trapped.

Get out. Get out. Need to get out.

Even with everything shredded and scattered by his fall into the Core and his time in the Void, his Soul remained. It broke like the rest of him, even if it held together a few seconds longer than his body. He shouldn't have survived when everything tore asunder. But the infinite darkness seemed to have strengthen his Soul, the Void fusing with it just like the rest of what remained of him. His Soul shattered into pieces, but continued to behave like a single whole. Even erased from existence and memory of nearly all who knew him, his Soul persisted and death eluded him.

He couldn't escape and he couldn't make it stop. He couldn't end it.

No more. No more. Please no more.

But there was… something. Two thin connections, stretched over an impossible distance and yet unbroken, reached from his fragmented Soul all the way to reality. Those thin threads of connection were… important. He couldn't remember why, what they were, or what purpose they served. His mind and memories were too frayed for that. The knowledge was scattered and lost.

He did realize that the connections might be his one hope. If he wanted freedom, the thin threads leading back may be his escape.

He tested them, stretching out and pulling on them. A pair of Souls. Physical bodies, both similar enough to his own that they could support his Soul if necessary. One felt more durable, but the connection to the other was stronger.

Have to escape. Have to escape. Have to escape.

He tried to tighten his grip on the stronger connection, pulling at the thread. He kept losing his hold though. Time was acting strange. Not in the Void, where time was always incomprehensible. The flow of time in reality was inconsistent and jolting the thread of a connection out of his grip. The connections, both of them, sometimes even vanished before reappearing once again. Someone or something kept messing with the space-time continuum.

He didn't stop. For a moment or an eternity, he kept grabbing and regrabbing the thin thread regardless of how many times it slipped away. It was the only connection he had to reality. It was an anchor in the chaos and static. It was hope.

Got to get out. Got to get out. Get out. Get out. Get out.

Thousands of years or the blink of an eye; how long he struggled in harsh and unrelenting darkness was impossible to judge. The constant onslaught of information from all time and all space only made it more difficult. But then it happened. Timelines stopped jumping around, twisting, and tangling together. And that let him finally gain a solid grip on the thin connection without it being ripped away again.

His mind remained scattered while his sanity frayed, so his thoughts were fragmented and confused. But he knew that if he followed the connection, it would lead out. So he pulled. He tugged and pulled on the thin thread stretched over the infinite distance.

He pulled harder and harder, trying to climb his way out of the Void. There was a physical body waiting for him. He just needed to overwhelm and replace the Soul in the way first. He could be free.

Some piece of him felt this was wrong, that he should let go before he went further. But it was only a single fragmented thought in the darkness. And he needed to escape.

No more. No more. No more. Too much.

So he held tight to the connection and pulled. And with each sharp tug, he used more power. And the harder he pulled, the closer he was to escape.

Sans tried not to flinch visibly at the sharp and almost painful way his Soul seemed to lurch. There were too many witnesses who would notice and worry. Papyrus would worry and that was absolutely the last thing he wanted to happen. So he hid the reaction just like always and kept his grin in place while he watched everyone else enjoy the barbeque for the rest of the afternoon. It wasn't as if the sensation was anything new.

He wasn't exactly the model of perfect health. Going through life with a single HP kind of had that effect. Not only could one solid hit take him out, any form of sickness could turn devastating or even deadly. Even sleep could only raise it temporarily above his base HP levels. But he hadn't died yet, so he figured the sensation was only unpleasant rather than dangerous.

It had been happening at random for quite some time, long before Frisk fell into the Underground. In fact, it began around a certain event that also marked the start of his more unique abilities. His "shortcuts," his ability to pause time briefly with enough concentration and energy… He was probably due something to balance out his minor abilities over space and time. A sharp and short jerk of his Soul once a month or so was a fair trade.

The thought made him pause. Shifting slightly as he leaned against the tree, Sans actually started counting. He hadn't realized it before, but they were more common than before. The unpleasant jerks of his Soul had grown more frequent since he left the Underground. The last one was only a couple weeks ago. The realization almost prompted language that he really shouldn't use in front of the kid. Or Papyrus.

As much as Sans didn't want to consider it, the fact they were growing worse probably meant he couldn't ignore them much longer. Even his laziness and apathy had limits, especially in the last several months. He just didn't like the poking and prodding that would follow. There was enough of that when he was younger. Monsters with single digit HP don't make it out of infancy and any professional healer freaked out and became overprotective the instant they realized. And Sans always ended up enduring every single test and exam they could devise before they'd let him go. The entire process frustrated him and he avoided anything resembling a checkup. But he might have to break that streak.

He'd have to find a new healer though. It been so long since he'd gone to one that Sans was fairly certain his old healer had retired.

But that was an annoyance to deal with another day. For the moment, Sans felt perfectly satisfied leaning against the tree in the backyard enjoying the afternoon. After emptying two fire extinguishers onto the grill, Papyrus and Undyne were dragged from cooking to a friendly volleyball game involving a few of the former sentries and Frisk. The competition became rather fierce once Undyne joined and Grillby took charge of salvaging the food, which was exactly what the kid intended when they invited Papyrus and Undyne to play. Frisk was always a smart child and had a knack for figuring people out.

Monsters wandered in and out of the large yard over the course of the afternoon. The dog sentries stayed for a while until even Greater Dog grew tired of chasing the ball around. Grillby made certain there was enough food before heading back to get his bar ready for the evening. Asgore showed up long enough to visit Frisk, but sharp glares and cold shoulders from Toriel eventually drove him off again. They were civil with each other now, but her patience with her ex-husband had limits. A few Temmies, a Tsunderplane that kept bumping into people, a couple of Froggits, Aaron, and MK all made brief appearances before leaving.

It made sense that everyone wanted to attend the barbeque. Even without the food and games, monsters loved any excuse to gather together outside. Generations trapped Underground ensured the appeal of sunlight and open skies didn't wear off quickly. Between eating his burger and watching the occasional chaos, Sans was perfectly content to nap under the tree while the sun warmed his bones.

The first time he realized that he actually felt happy and even some hope surprised him. He'd embraced that numb apathy in the face of his helplessness for too long. He'd forgotten what it was like to be optimistic. Even making it to the Surface wasn't enough to erase his doubts. He was certain he would wake up one morning back in Snowdin with no solid memories of his better life. But as months passed and nothing happened, he let himself start enjoy their new life with the shadow of suspicion growing fainter.

He would probably always worry that his life would Reset and he'd fall back into the loops where none of his actions mattered. But he knew that Frisk wouldn't do it on a whim. He knew the kid and what kind of person they were. They'd promised. If they ever chose to Reset again, it would be because the situation was dire and any other choice was far worse. That was as much reassurance as Sans would ever have and it was enough.

"SANS!" called Papyrus, pulling him out of his light snooze. "DID YOU NAP THROUGH THE ENTIRE AFTERNOON?"

Stretching in a way that made his joints pop, he climbed to his feet, "nah, bro. i caught your game with undyne. it looked like you guys were having a ball."

"UGH, THAT WAS TERRIBLE!" groaned Papyrus.

"it made you smile."

"I KNOW AND I HATE IT!" he said as he pulled Sans to his feet.

Chuckling slightly at his brother's reaction, Sans took a moment to see who was left. Most of the yard was empty since the barbeque was winding down. Toriel and Alphys, for once wearing more casual clothes rather than one of her countless lab coats, were starting to clean up while Undyne took down the volleyball net. Papyrus would probably try to talk him into helping. Sans was already debating if the chance to exchange puns with Toriel would be worth the effort of picking up a plate or two.

A tug at his sleeve told him exactly where Frisk wandered off to. Messy hair and a striped sweater, they looked so much like they did when they first fell into the Underground. They gave him a shy smile as they handed him a small bottle of ketchup from the picnic table. Sans ruffled their hair, producing giggles. The kid really knew how to get on a guy's good side. Sans slid the bottle into his pocket for later.

"WELL, SINCE YOU LAZED THE DAY AWAY, YOU SHOULD BE PERFECTLY WELL-RESTED ENOUGH TO ASSIST US IN STOWING EVERYTHING AWAY!"

"i don't know about that, papyrus. i might need to rest up a little before trying something so strenuous. You wouldn't want me to pull a muscle, right? i don't have a lot of them to spare."

Frisk giggled while Papyrus sputtered in frustration. The human's sense of humor was definitely heavily influenced by living under the same roof as Toriel, though Sans liked to think he had something to do with it. It was such a shame that Papyrus never appreciated puns the same way. Or at least couldn't bring himself to admit to enjoying them. But tossing out a pun wouldn't be half as fun without Papyrus complaining about it.

"SANS, HONESTLY, IT'S THE LEAST YOU CAN DO!"

"you're really underestimating how little i can do."

"SANS!"

Frisk didn't even try to hide their laughter as Papyrus stomped his foot in annoyance. Even Toriel struggled to suppress a small chuckle, the other monsters now paying attention to the pair. Sans loved his brother and he was the coolest person he knew, but there was just something so fun about messing with him a little.

"all right, bro, i'll st—"

Sharp pain cut off his words, the pulling sensation on his Soul stealing his breath away. Not again. It was too soon. Why was it jerking again? And it was worse than before. It hurt so much worse and was lasting longer. He couldn't hide his reaction this time. He could only grit his teeth and try to avoid doing more than hiss in pain as he waited for it to stop.

Then the pressure on his Soul stopped as suddenly as it started. Trying to catch his breath, Sans realized he must have shut his eye sockets at some point and reluctantly opened them. The first thing he saw was Papyrus kneeling right in front of him, one hand on Sans' shoulder to steady him and a worried expression. Which was the last thing he wanted to happen and what he tried so hard to avoid. Frisk was leaning around the taller skeleton with a frightened look and the sound of hurrying feet didn't really help things. He didn't want to scare everyone like this.

Of course, if he was honest with himself, Sans was scared too. Something was wrong with him. Seriously wrong. And it was clearly getting worse. He couldn't ignore it this time.

He vaguely noticed that he was clutching at his chest with one hand. He must have grabbed at where he felt the pain in his Soul. Sans couldn't bring himself to let go yet.

"SANS? WHAT HAPPENED? ARE YOU ALL RIGHT?" asked Papyrus uneasily, staring at his brother carefully.

He had to reassure Papyrus. He couldn't stand seeing Papyrus worrying over him. Even if he didn't know what was happening, he had to tell his brother that everything would be fine. He tried to give them a reassuring grin.

Trying to keep his tone calm, Sans said, "…papyrus, i—"

His Soul lurched again, stronger and more painful than before. And it didn't stop. He couldn't breathe, couldn't move, and couldn't think. He heard voices, but they sounded muffled and he couldn't understand the words. Whatever force it was kept pulling and wouldn't stop. The pressure kept increasing.

Then something gave way. The pulling sensation overcame whatever was holding it in place. Whatever was holding his Soul in place. It ripped him away. His grip on his body stretched and grew thin as he was pulled away. It didn't snap completely, but the connection to his body grew faint and weak.

Was he Falling Down? Was this death? Was this what dying felt like? Frisk would probably know.

Sans couldn't tell if he was falling or being yanked up. But his Soul was plunging into darkness.

Dark. Darker. Yet darker.

The first hint something was wrong was when Sans broke off from his banter with his brother, the sudden cut to silence enough to draw attention. Alphys had turned to see the shorter skeleton with his eye sockets pressed closed, wobbling a little on his feet, and clutching his chest. It lasted several seconds until his breathing eased and his fingers were no longer digging into the fabric of his t-shirt. By that point, Papyrus and Frisk were worrying over him and Alphys, Undyne, and Toriel were hurrying across the yard.

And as Papyrus tried to coax an explanation from his brother, the second piece of evidence of impending doom struck. Alphys was close enough to see his expression go from a shaky reassuring grin to pained shock in an instant. His eye-lights shrank to pinpricks before extinguishing completely and his body went limp like cutting the strings of a marionette. Papyrus was the only reason he didn't hit the ground, his arms moving faster than gravity could make him fall.

What followed was a whirlwind of worried and mildly panicked chaos. Toriel immediately summoned up her green healing magic, the undiscussed knowledge about his low HP looming in everyone's minds. But Alphys knew that wouldn't help much. Sans would be dust if his body was physically damaged by what happened. She didn't mention that, however. She just followed closely as they hurried to get him help.

While human bodies were composed of greater amounts of physical matter and a cocktail of chemical reactions that required a vast education in biology to understand, monsters were composed of hope, love, and magic. Basic healing magic could handle most problems. Certain diseases and more serious injuries, however, required more skill and training than the average monster possessed. While treating humans required someone with a doctorate and a lot of pointy objects, monsters went to healers and their doctors tended to focus on other branches of science.

Well, a lot of healers outside of the smallest communities did tend to go ahead and get a doctorate anyway. More serious injuries, especially those not immediately healed, and more unusual illnesses required a proper education to identify and handle. Treating a fire elemental was different than treating a mammalian monster and it was completely different handling a skeletal patient.

Unfortunately, even with how long they'd been on the surface, they hadn't really built a proper hospital in Newer Home (Asgore's naming skills had not improved with time). The prevalence of healing magic meant it wasn't a priority. But there was at least one small clinic that Undyne and Papyrus passed regularly on their jog, a location close to them.

Technically the clinic was closing for the day, but they didn't let that stop them. Dr. Sola, apparently originally from a small community in a cavern branching off from Waterfall, agreed to take a look when she saw a worried group that included the former queen and a rather forceful Undyne.

She was a more avian monster, looking remarkably like the colorful peacocks with their elaborate tails. You know, if the spots of their fan-like tails were actually eyes and their wings included fingered hands. Dr. Sola seemed professional and competent as she ushered them towards one of the larger rooms in the back. And rather attractive if Alphys was honest. But something about the avian monster made her feel anxious about the situation.

They weren't led to the smaller rooms meant for checkups and treating smaller monsters for minor issues. The larger exam room held more medical equipment along the mint-green walls. The exam table was also larger. The location was clearly intended for larger monsters. Dr. Sola probably brought them back to this particular room due to the extra machines in place. Or because of how many taller monsters were in the group bringing her patient in.

Papyrus seemed reluctant to release his brother and leave him on the exam table as Dr. Sola directed. Alphys didn't blame him. Sans didn't look any better. His eye sockets were pressed tightly closed while a pained grimace dominated his face even in his unconscious state. His breathing was labored and fast, as if the skeleton was performing extreme physical exertions rather than lying on the exam table as the healer pulled off his jacket. And while mostly limp, there was the occasional twitch of the head or hand that gave the impression that he was trapped in a nightmare. Alphys couldn't help mentally filing all these symptoms away, her mind considering and rejecting the possible causes.

"Were there any symptoms before your friend collapsed? Lack of energy, sudden weakness, aches, anything?" asked Dr. Sola, carefully pulling off his white t-shirt.

"He seemed to be in pain shortly before hand," Toriel described. "He passed out before we could ask about the cause, but it was sudden and the pain seemed focused in his chest."

Nodding distractedly, Dr. Sola pulled out a small, black, rectangular device. Alphys recognized the basic Check Scanner as a very useful diagnostic tool. While some details could be figured out by checking with magic, that method could easily be colored by preconceptions and influenced by the one performing it. The Check Scanner could provide accurate, clinical, and precise readings of a monster's stats. Their AT, DF, HP, and so on. That information could reveal a lot of baseline information about a monster's overall health at that moment, especially when compared to their base stats. Any half decent healer would have a scanner in their arsenal, though Alphys vaguely noticed it was an older model.

She frowned at the display, her beak opening and closing without speaking a word. Dr. Sola glanced between the Check Scanner and the unconscious figure on the exam table and back again. Her feathers ruffled and all her eyes blinked rapidly. Everything about her posture screamed shock and confusion.

"That… that can't be right. His base HP… That's impossible. Infants don't have it that low. That's—"

"THAT'S NORMAL FOR SANS!" Papyrus interrupted. "HE'S ALWAYS HAD VERY LOW HP! THAT'S NOT WHAT'S WRONG WITH MY BROTHER!"

Dr. Sola didn't look completely convinced by the skeleton's words. She kept looking at the scanner, entranced by the information on the screen. She just couldn't seem to get past the single HP. Having someone reduced to that by injury and illness was quite different than having it as their base level.

"Poor general health and an inability to regain consciousness? I'm sorry to tell you this, but the symptoms seem to indicate he's Fallen Down."

That declaration hit the group hard and in a variety of ways. Toriel gasped and covered her mouth in horror. Frisk stared at Sans with an unreadable expression, biting their lower lip. Undyne appeared furious, but with no one to direct her anger at. Of course, Alphys knew there was more to her emotions than just fury. Some of that anger was worry and helplessness.

Papyrus' expression was more difficult to read than it should be. There was stubbornness and annoyance. And a refusal to lose hope. He was almost glaring at the healer.

And Alphys… She might be shy and her confidence might still need work, but at that moment… something was bubbling up inside her.

"YOU'VE MADE A MISTAKE," said Papyrus slowly, an edge to his voice making it nearly unrecognizable coming from the taller skeleton. "SANS HAS NOT FALLEN DOWN."

Softening her gaze slightly, Dr. Sola said, "I'm sorry about this, but denial won't change the facts. Your brother was never very strong by the sounds of it and you must have at least suspected this would happen someday. Sometimes a weak or weakened monster will Fall Down and there's nothing anyone can do to help them. I'm so—"

"HE HAS NOT FALLEN DOWN," interrupted Papyrus. "I KNOW WHAT THAT LOOKS LIKE. IT HAPPENED WITH MRS. DRAKE AND SEVERAL OF THE OLDER DOGS. I SAW THEM. THIS ISN'T THE SAME THING. YOU'VE MADE A MISTAKE AND THEY HAPPEN SOMETIMES, BUT YOU NEED TO HELP HIM."

Alphys remembered. Back in the days of her Determination experiments, when she sent out a request for monsters who'd Fallen Down, several came from Snowdin. While it was a while back, it was still recent enough that the skeletons would have been living there. It was a small and close-knit community that would have been shaken by such events. Papyrus would have certainly seen and remember what happened. He was smart enough to recognize the same thing Alphys did.

"Your brother only has a single base HP and cannot be awakened," Dr. Sola said in a slow and firm tone as if speaking to a child about an obvious subject. "The simple fact is he's Fallen Down. Denying it will only make it more difficult for you in the end."

"And w-what about the s-symptoms you're ig-ignoring?" asked Alphys, narrowing her eyes. "Th-the ones th-that contradict your d-diagnosis?"

All of Dr. Sola's numerous eyes blinked briefly before staring at the reptile scientist. Everyone was looking at her now. Alphys felt herself start shaking and sweating from being at the center of attention. She never liked this. But she couldn't back down. Not when everything in her rebelled against what the healer was saying and doing. Not when keeping quiet could harm a friend.

A pair of scaly hands settled on Alphys' shoulders and took a deep breath, some of her anxiety easing. Her girlfriend would support her. And her friends would too. Alphys could do what she needed to do. She could handle this. And she needed to speak out. She couldn't keep quiet.

Stay brave, Alphys. Remember, just imagine what Undyne would do and just do it less violently.

"The onset of everything was too f-fast," she continued. "M-monsters don't Fall Down like that. Unless the cause is an injury, Falling Down isn't so s-sudden." Alphys took another deep breath. "There is increasing lethargy for hours or even days prior to slipping into an unawakenable slumber. They don't just collapse without warning. And when they Fall Down, they are completely still and limp, their breathing is slow and shallow to the point it can be difficult to detect, and in many cases appear to have paler skin and duller fur or feathers. Now the last wouldn't apply to a skeleton, but Sans has shown small intermittent movements and his breathing is labored. Even with that rather rudimentary examination that you barely attempted, you should have realized he hasn't Fallen Down. You're supposed to be a healer. You're supposed to do better than this."

Dr. Sola gaped at Alphys. She didn't cringe back. The anger had grown as she'd spoken, pushing past her anxiety. Her frustration with the healer and the situation and her certainty that she was right even managed to spur Alphys forward enough for her stammering to ease off.

"What?" said Dr. Sola, her feathers ruffling. "Who do you think you are speaking to me like this, Miss—?"

"Dr. Alphys," Undyne interrupted, her tone making it clear she was baring her teeth at the healer. "Former royal Scientist and my girlfriend. So be careful what you say."

No matter how many times she heard it or what the circumstances might be, hearing Undyne call her "girlfriend" still made Alphys blush and feel so warm inside. She still couldn't believe her luck.

But even Undyne defending her honor wasn't enough to completely distract Alphys from the grave situation. Sans was still out cold for an unknown reason and Dr. Sola seemed content to write the entire problem off as the natural result of his low base HP. She didn't want to look any further for a cause. But the healer wouldn't get away with just the bare minimum.

"You can't make a d-diagnosis just by checking a monster's stat," Alphys continued. "That's just a starting point. You didn't even look at his Soul or check his magic levels. Can you st-stop being lazy and do your job? …P-please?"

Dr. Sola sighed tiredly before giving a reluctant nod. Alphys tried not to completely collapse and start hyperventilating. She'd hit her limit of courage for the day.

Manifesting your or someone else's Soul was one of the simplest spells that all monsters learned at a very young age. Without learning that skill, without learning how to locate and manipulate the source of your magic, how could you expect to master other forms of magic? Even though the removal of Sans' shirt and jacket exposed his ribs, his Soul would remain invisible to the eye until someone summoned it forth.

And while a monster's stats could provide some basic information, a Soul was the very culmination of their very being. Manifesting his Soul and examining the current state of it would provide more information. How could anyone expect to make a real diagnosis for Sans without enough information? That was common sense.

And while a conscious monster might be able to resist someone trying to manifest their Soul, Sans' unconscious state meant it should be easy to summon forth. It should be easy for even the most unskilled use of magic to achieve.

But when Dr. Sola tried to summon his Soul, nothing happened. Her beak twisted into a frown as she tried again. Her efforts seemed to have no effects. Sans remained in his troubled unconscious state and his Soul didn't appear.

"Can this healer do anything right?" growled Undyne.

"I… I don't understand," Dr. Sola said, her numerous eyes gawking at the small skeleton. "His Soul… It's there… It has to be. He would be dust without his Soul. But I can't… It's there, but it's not. I don't understand what's happening."

She dove for a machine in the corner and wheeled it over to the exam table. There was a large sensor pad connected to a tangled cord that Dr. Sola placed on his rib cage. She hit a few switches and twisted a dial, trying to adjust the machine. The screen showed a list of numbers and the image of a Soul. But the numbers and image kept flickering, going blank before reappearing.

Dr. Sola gawked at the results in absolute shock at the results. Alphys couldn't blame her for that reaction. This wasn't normal. Something was happening that the standard equipment couldn't properly detect and measure, but it still showed enough for Alphys to recognize that it wasn't normal. This was so wrong and terrifying.

"I… I don't understand. This doesn't make sense," Dr. Sola said quietly. "I… don't know what's going on."

She couldn't wrap her mind around the impossibility. Alphys could see it on the healer's face. Whatever education she received about treating patients never prepared Dr. Sola for this and she didn't know how to adapt.

Alphys wasn't a healer. She was better with creating and building technology than using her relatively weak magic. But due to her Determination experiments and the Fallen Down monsters that her efforts twisted into the poor Amalgamates, she knew quite a bit about Souls. She knew more about how they worked and their limits than most monsters could imagine. And she'd created a lot of specialized equipment to detect, monitor, and record the condition of Souls. Equipment far more sensitive and effective than anything else available.

Dr. Sola couldn't do anything for Sans. That was clear. But maybe Alphys could use her past mistakes to help.

"Th-thank you for your t-time, Dr. Sola," she said. "P-papyrus, your car's fast, right? We need to head b-back to the entrance to the Underground and go to my old lab. If I can get to my equipment, I m-might be able to f-figure out what's happening and help Sans."

Papyrus didn't need any further prompting to rush past the still-in-shock healer and scoop up his brother in his arms again. Undyne grabbed the discarded jacket and shirt while giving Dr. Sola a final sharp look. The rest of them quickly filed back out the way they came, a new destination in mind.

Alphys, her mind already racing ahead to her old lab and the available equipment stored there, vaguely noticed Frisk's expression as they kept glancing at Sans. They looked rather… Determined.

So… Yeah, I'm handling the Gaster situation a little differently than I did in my last "Undertale" story. It is probably going to be a little longer too. I hope you don't mind.

I'm also going to explore the issue of Boss Monsters a little too (though there are already hints on the topic in this story). In the game, the only ones we know for certain are Boss Monsters are Toriel, Asgore, and most likely Asriel (before the Flowey incident). Now, we could assume that means that all Boss Monsters are goat-like entities, but that's not really a good enough sample size to confirm it. Those three are part of a single family and similarities in appearance and Boss Monster-ness is to be expected.

But I'm going for a different approach than "Boss Monsters are always goats." While the topic will be explored further later in the story, I'm working with the idea that being a Boss Monster is something you notice about the Soul rather than the physical body. After all, one of the defining traits of a Boss Monster is that their Soul lasts a few seconds after death. But as I said, that will be discussed later in the story in greater detail.

Anyway, I hope that you like the story so far. And I hope that at least some of the elements I have in mind will surprise you. Remember, reviews are always appreciated.