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Undertale: War of Souls

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Undyne, the greatest hero of all time, was finally here. She was going to stop the human. She was going to stop the murders. Once she was through with them, everything would be okay.

        These were the thoughts running through young MK’s head, the monster peering out at her from a cluster of kelp and rocks as he watched the woman fight. She’d even transformed into a brand new form for this! She’d completely healed from getting nearly cut in half and was even stronger than before! Yes, that whole situation had been scary enough as it was, but at least Undyne had a handle on things. She’d defeat the human! She had to! She was Undyne the Undying after all!

        But then everything began to go wrong. He had tried to ignore it, but as he continued watching, the boy began to notice that Undyne was... melting? Was that even possible? It had to be a trick- She was just sweating! Yeah! She was just sweating and it looked kind of like she was melting! The battle had been going on for a long while, so it wouldn’t be surprising if she was, right?

        But soon it became obvious that Undyne was not sweating. MK was not seeing things. Undyne really was melting... And it was a horrible thing to watch. The fallen hero, laughing in pain while trying to continue the fight, only for the human to merely watch her as she slowly but surely became nothing more than a pathetic puddle on the ground.

        His hero was gone.

        Within seconds.


        And she wasn’t coming back.

        Frozen in shock, MK stayed hidden, the boy wanting to run away and cry but unable to do so. Fear kept him in place. He couldn’t move. He couldn’t. Not with the human still here. The human would kill him if they saw him. He didn’t want to die. Not yet. Even with such horrible things happening, he didn’t want to die.

        Instead, MK watched the human stare at the puddle, only to begin grinning and snickering and muttering something about how they’d ‘finally done it.’ It was strange to the young monster, especially when said human seemed to begin having a strange conversation with themselves, but then they eventually moved on, and thus they left MK alone.

        ”...My parents... I-I should-“ Quickly, the boy had pushed himself up to his feet, only to head across the bridge Frisk and Undyne had been battling on just moments ago. He had to find his parents. He had to find his big sister. He couldn’t just sit there and watch them die too! He needed to at least warn them about the human!

        But then the boy stopped running and began to think. He couldn’t just warn his parents about them. They wouldn’t be able to do much. They weren’t royal guards! And not even Undyne the Undying could stop them... What could he... Yes.

        MK didn’t know many people who were stronger than Undyne, but there was one monster that everyone knew could beat just about anything. He’d been Undyne’s trainer. He’d fought in the war against humans and monsters. King Asgore. Yes. King Asgore could help them! And thus off MK ran. His destination? The Castle of New Home.

The run there was filled with MK tripping over himself in the beginning, but he was eventually able to catch his balance and take off. Even though he didn’t have arms, the boy made up for that with his speed and agility, and thankfully, that was enough to get him to the castle, even if he’d tired himself out by a great deal. MK had taken little breaks in between the running, but terror had pushed him to keep going. He had to get there before the human did, especially considering they had advantages he didn’t in terms of traveling. Even with his kind of speed and agility, MK had needed to take paths that were friendly to armless folk, but at least he’d arrived, and right on time, for it seems the human had shown up right before him.

        Walking into the castle, the boy was surprised to find that the first thing he’d come across was some homely setting, one that looked just like any other house except larger. He would have walked inside right away had he not seen the human walk by one of the windows, and quickly, the boy ducked down and pressed himself up against the wall right next to the door. MK had never been here before, so he didn’t know if this was even the right way or not. At least he could guess that it was considering the human was here. They seemed to be heading straight for Asgore after all...

        Biting his lip, MK listened to the human rummage around, occasionally hearing the sound of them speak. Their voice was kind of airy and quiet, but it was also shaky, only seeming to cease shaking whenever the human seemed to be speaking to... another voice. Who was that? Who was the human talking to?! And more importantly, why did this person sound like they knew them?! Were they working with them?! Were they helping to kill everyone too?! It was a surprising thing for MK to hear, but he couldn’t confront them. No. He could only tell Asgore what was happening, and in order to do that, he’d just have to wait for a good time to get ahead of them.

        Soon enough, MK then heard the human open the door to another room, said door closing right behind them from the sound of things. Finally. An opening, and now, using his mouth, MK was able to open the door to get into the house and finally peer inside. There were three ways he could go: the hallway to the right, the living room to the left, and the stairs right up ahead. Already, MK had decided that his best bet was probably the stairs, though sadly, those were blocked off via chains.

        Like that was going to stop him.

        MK then prepared to completely step inside when he heard the door from before open, the boy quickly backing out of the house, though he left the door open just a crack. He hoped the human wouldn’t come this way now that they were out of that room, but thankfully they’d instead headed deeper into the house, but not before unlocking the chains with the keys they’d just acquired. Better to get the chains out of the way, he guessed. But then, the human headed into the room further down the hall, and once they were inside, MK took action.

        Swiftly, the boy darted across the room and down the stairs, his feet barely making a sound on the wooden floor as he did his best to not only be quick, but quiet. This, unfortunately, caused him to lose his balance much quicker than usual, and thus he’d nearly tripped over himself on the way down. Dumb luck was the only reason he hadn’t fallen. That and he’d whipped around and sank his teeth into the railing, which of course made way more noise than he had desired. That lead to him quickly getting back to running without looking back, dashing all the way down the remainder of the stairs and through the many halls, until finally, he’d made it.

        Asgore's throne room.

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”Yo Asgore! Mr Asgore-!” The second he’d tried to slow to a stop so quickly, the boy ended up tripping once again and falling onto his face, only to try and pull himself back up like he always did. This time, however, he didn’t have to get up on his own, for soon enough, Asgore had come over and picked the monster up himself.

        Oh? Howdy there, little one. That was quite a fall.” It was strange being in the presence of someone so much larger than him, but at least this wasn’t extremely new; Asgore had once come to his school after all... Would he even have school after this? Who knows...

        ”Mr A-Asgore- I need- I need to tell you something- I-“ MK could barely get the words out, especially after running for so long. He was out of breath and downright terrified. The human was heading this way! Could Asgore handle them? Yes. Yes he could. He had to! He was sure of it! But... “T-The human- It’s coming- It’s here-!”

        The second MK mentioned the genocidal human, Asgore’s expression transformed into that of a grim one. He already knew the human was coming. He’d heard about them through the guards. That was why he had ordered everyone to evacuate. That was why he had ordered only the strongest of his guard to try and hold them off. But if he was the last one standing, then he would take them on, even if he was unsure of whether or not he was capable of fighting something so fierce.

        ”...Where’s the human? And where is your family? Did they evacuate?” Asgore asked, MK then proceeding to gather up some air to speak.

        ”T-they’re in your house, I-I think. A-and my family went to the Capitol, but I... I didn’t-! I wanted to see U-Undyne fight the human, but she...!” Quickly, the boy had gone from merely crying and wheezing to full-on sobbing, grieving for his hero after she’d died in such a gruesome way. And to think she’d died to save him too... Maybe part of this was somehow his fault... But he didn’t have time to think that way. Not right now. Not when Asgore was here.

        It surprised the boy when he was suddenly picked up and hugged, but he quickly melted into it, even if it was kind of weird; he needed a good hug right now, and it seems King Fluffybuns was perfect for hugs.

        ”Shhh... Young man, you were very brave, and you have done me and monster kind a great service in telling the location of the human. Thank you.” The King didn’t bother in wiping away the boy’s tears, not when he seemed to need to cry, plus it would be better for him to cry now instead of later considering he would need to hide. But Asgore couldn’t wait around and comfort the boy all day; if what he said was true, then the young monster would need to leave; he wouldn’t let him witness another potentially dusty battle.

        ”I-I... you’re- welcome...” the young monster hiccuped, only to look up at the King with puffy eyes.

        ”There there,” Asgore hummed, patting his head with a smile on his face. “You’ve done what you can. Now please, let me get you some tea.”

        At the sound of Asgore’s statement, MK couldn’t help but give him a confused look. Tea? Now? “Why? The human-!”

        ”The human will come, and when they do, I will take care of them. But I can fetch you a quick cup of tea in the meantime. It won’t take long.” With that, Asgore then sauntered out of the room, heading to a path off to the side, a path that MK hadn’t noticed before actually. In fact, now that he’d thought about it, he didn’t think it was there before. A secret passage, perhaps?

        ”I remember seeing you once at your school. You were extremely enthusiastic. Your name is MK, right?” asked the large goat monster, only for MK to suddenly nod excitedly.

        ”Yeah! That’s me!” exclaimed the boy, ecstatic that King Asgore had remembered him. “Well that's just a nickname, but it's an awesome nickname! The Magnificent MK, future Royal Guard and defender of monsters!”

        Asgore couldn’t help but let out a hearty laugh at that, only to eventually set the boy down. “I like your enthusiasm. Now, for that tea...”

        The room they were in looked like a small, homely kitchen, greyscale like the King’s house, but still feeling like a nice little room that one could live in comfortably. There was a small table, an oven, and many cabinets, and once Asgore opened one of those cabinets, it became clear that they were stocked beyond belief, that particular cabinet being filled with tea bags.

        "I would brew some fresh, warm Golden Flower Tea, but this will have to do for now," said the monster as he turned on the faucet to fetch some water, all while humming as he did so.

        As MK waited, the boy simply swung his feet back and forth in the seat, not knowing what else to do while Asgore worked. "That's okay. You really don't have to."

        "Of course I don't. I could have simply left you here and left to face the human alone," said the king, only to eventually turn around with a nice cup of cold tea, which he set down in front of MK. "But I chose to make you tea. Tea has always been something that calms me, and you looked quite parched. So please. It's on the house."

        Humming a bit in a nervous manner, MK then sat up before picking up the end glass with his mouth, only to tip it back and begin drinking the tea before setting it down once again. "Thanks, Mr. Asgore. You're the coolest." He may as well thank Asgore somehow, and he was glad he did, for the monster certainly seemed happy about that.

        "You're welcome. Now, please remain here. I will wait for the human. If anyone enters this hall and doesn't announce their presence, run." It was a lot to say to a child like MK, hinting that he may not make it after his hero and many others had died, but it was necessary all the same. "I will do my best to keep everyone else safe, but... In case I fail, please hide. All right?"

        MK's expression had quickly transformed into that of a grim one after that, but even so, the boy didn't want to let Asgore down, plus he knew he should have faith in the King of Monsterkind. Asgore was strong! He'd fought many humans back when they had warred against monsters on the surface! Surely he'd be able to take on some human punk! Yes, that's what he'd do. He could do it! MK had to believe in him! "I'll do my best, Mr. Asgore! Go kick their butt! You can do it!"

        At the sound of the monster child's encouragement, Asgore couldn't help but smile at the young boy. "Thank you. See you soon."

        And with that, he left the room, leaving MK all alone once again. It felt... lonely after he'd left, as though the grey of the room had sucked out what little emotion Asgore had left behind. Nonetheless, tea couldn't keep the boy company anymore, especially after he'd drank all of it. This allowed him to think about the situation more than he already had, and so the monster began the downward spiral.

        MK didn't know a whole lot about humans. All he'd learned was that they'd been the ones to seal monsters underground and that only human souls could break the barrier. Oh, and there was the First Fallen Child, who apparently was part of the reason why souls were getting collected. The story about the First Fallen and Asriel was... sad. No wonder Asgore had declared war again. At least they'd gotten close; they only needed one more soul until Asgore could break the barrier, but... could Asgore take this human's soul? They were so ruthless... He truly hoped Asgore would win, but nonetheless, MK couldn't sit still anymore. He had to walk around.

        Thankfully, there was another place he could go other than right to Asgore, and so, MK took the chance and began heading down the other hall, humming a bit in order to try to lift the mood. After all, the hallway was long, dark, and creepy, and frankly, MK didn't like it. If only there was a torch...

        As the boy walked along, he eventually noticed a glow coming through one of the many rooms in the hall. It was strange in his eyes, mostly because a lot of these rooms were either empty or filled with boxes, and none of them glowed. Besides, he was itching to have something to see with. And who knows? Maybe another monster was in here? That could always be the case.

        Quickly, the scaly little monster headed towards it, sadly tripping over himself in the beginning, but he quickly got up and arrived at the room where the glow was coming from. And what he saw had caused the boy to stop dead in his tracks. There they were.

        The six human souls.

Chapter Text

Seven souls. That was the total needed to break the barrier, a powerful forcefield made up of magic that had continued to exist for hundreds of years. It was an amazing force, the barrier. Honestly, MK wondered if the humans had thought the barrier was impenetrable. Had they really thought that monsters would stay down there forever without looking for a way out? Even if humans did have more powerful souls, they weren't as magic-savvy as monsters. They should've never underestimated their ability to find a way out.

        Now they were close. They were so close to escaping. All Asgore needed was the murderous human's soul, and then they could finally see the stars. It was... actually kind of stressful for MK to think about, mostly because if one human child was this bad, then... what would the other humans be like?

        Slowly, the curious boy made his way into the room, staring at the seven jars before him as his eyes scanned the souls. While the boy knew some things about monster/human history, he was very clueless when it came to, well, literally anything else about humans. MK hadn't even known what a human looked like until now! He really was clueless, wasn't he? But he couldn't think like that; not right now. Besides, it wasn't like anyone else didn't know what a human looked like; he couldn't be the only one if the human had gotten so far. But nonetheless, once he was in front of the jars, the monster began to examine their contents, even if there wasn't much to examine.

        The first thing MK found interesting was each soul's colors and how they all sported a different one, neither ever having the same color. The only ones that were comparable were the cyan and blue ones, but even then they were distinctly different, the cyan soul being much brighter and easier to see compared to the deep blue one. He found it neat that humans had their own colored souls, especially considering monster souls were all white; it actually made him question what color his soul would be if he was a human, but he didn't want to think much about the human part, not when one was trying to annihilate all of monster kind.

        Nonetheless, there wasn't much to say about the souls; they were simply floating hearts trapped in strange jars, floating hearts that apparently possessed so much power that a monster would become extremely powerful...

        That was it.

        "The souls!" MK suddenly blurted out, only for his tail to quickly swing upwards and cover his mouth. He didn't know if anyone could hear him from down there, but he didn't want to take any chances. This place was creepy enough as it is, and he wasn't even thinking about the fact that he was in a room with the souls of dead humans. No. He was choosing not to think too much about that. All he had to do was focus on the power they held and getting that power to Asgore. If the souls really were powerful enough to break the barrier when combined, then Asgore... A Boss Monster with six human souls would certainly be able to take down one human. He was sure of it.

        Quickly, the boy began hopping up and down on his toes, trying to figure out just how he was going to get the souls to Asgore. After all, the jars were about half his size, and without arms and hands, he'd certainly have a hard time getting them to the King so that he could use them. But even so, he had to try, and eventually, he got an idea. He could carry them with his tail.

        Proud of his brilliant idea, MK then circled the jars, only to eventually pick the yellow soul to take with him first. After all, yellow was his favorite color, and it didn't matter which order Asgore absorbed the souls, or at least he didn't think it did. Besides, maybe when he got one soul to Asgore, the king himself would get the rest. Yeah. It didn't matter what order he got them to Asgore. He just needed to get them there.

        At first, MK made the attempt to wrap his tail around the jar in order to properly pick it up, only to find that sadly, his tail wasn't at all long enough to wrap around a jar so large. Geez, how large did these jars need to be? The souls weren't that big. Were they just that powerful or something? All of this really was confusing to the boy, but when he couldn't wrap his tail around it, MK decided to instead try and push the jar along.

        Getting behind the jar, the monster began to push it forward, surprised to find that it was much heavier than he'd anticipated. After all, the jar may be large, but there was nothing in it save for a soul, and those things were floating in it! They couldn't be that heavy, could they?! Apparently, they could be, and while MK was making progress, he certainly wasn't pleased with just how slow he was going. If he wanted to get these to Asgore before the human arrived, he had to go faster. That's what lead to MK pushing harder than before, and that is what lead the jar to topple over and break.

        This definitely came as a surprise to MK, and it certainly also happened to be a bit of a scare for him as well. After all, he wasn't super knowledgeable on human souls, and he certainly didn't know what would happen now that one was outside of its jar. Panicking, the boy stared at the soul and anxiously circled the broken jar, almost as if he were somehow inspecting the soul for any sort of weird reactions. Thankfully, the soul did nothing more than float above the jar without a scratch on it, the yellow hue pulsing ever so slightly as it did so.

        "Whew. That was close," breathed the monster, only to look back down at the yellow soul before taking a glance at the exit. He'd been so close in getting the jar and soul out in one piece, but it wasn't nearly enough. He needed to get it straight to Asgore, and it was clear that he couldn't do that now, unless...

        "Hm... You can carry souls, right?" he asked himself, only to begin thinking with a frown on his face. He honestly had no idea. After all, it wasn't like the boy paid much attention to these kinds of things in school, especially when he figured he'd never see or interact with any human souls. So much for that... But the royal guards had to have gotten them in that jar somehow, right? They had to have handled them somehow, right? He could probably touch them, so long as he didn't absorb them, and with it floating, it would be much easier to carry.

        And so, without a second thought, the boy wrapped his tail around the soul, only to suddenly feel a warmth spring from the appendage. At first it felt nice, but that nice feeling quickly vanished as it transformed into a warmer and warmer sensation, only for the boy to begin to feel as though he and his tail were burning. He tried to release the soul, but he couldn't. Heck- He didn't even know where he was! Where was he- What was happening?! He didn't know, and within moments, the boy had gone from seeing a blinding light to viewing nothing but darkness.

        It was strange, floating in the dark like this. MK didn't like it honestly, especially given the situation. He knew what needed to be done. He knew how dire their situation was. So what was he doing here?!

        Eventually, MK found his footing and was able to land on what felt like solid ground; even if it all still looked like darkness, at least he could walk now, though where to walk was a good question. After all, there was no indication as to where he should go, or at least their wasn't until he spotted a strange yellow glow in the distance.

        Once MK had picked up the yellow glow, he'd begun heading towards it, first merely fast-walking, but then he'd begun running. "Hello?!" he called, desperate to reach the glow. Thankfully, he was succeeding, for the closer he got, the brighter it got, until eventually, he could make out the shape of a... person? No. That wasn't a person. Not a monster person at least.

        That was a human.

        Before he could skid to a stop, the silhouette had turned to him, and quickly, they'd begun to grow brighter and brighter until MK could no longer see. He didn't understand what was happening; the glow was so unusual, as was the extreme warmth that came with it, but at least he wasn't the only one in the dark, even if that darkness had begun to fade. He tried to call out to her, yet the sudden blinding light drowned him out. And then suddenly, he was back in the room, lying on the floor while facing the broken glass.

        "Ow... What just happened?" He could barely remember what he’d just done to get here. He’d broken the jar, yes. The jar with the soul in it... wait...

        ”The Soul!” The boy then suddenly pushed himself up into a sitting position, only to shake his head as he looked around the room in a desperate attempt to spot the yellow soul. “Oh gosh oh gosh- Asgore’s gonna kill me-!” No. Worse. The human was going to kill Asgore. He couldn’t let that happen!

        Within seconds, MK was on his feet, staring down at the glass and then looking towards the remaining five souls. Asgore could use these five to take down the human, right? Then they could go looking for the yellow soul, right-?

        ’Don’t touch them.

        The sudden voice in his head quickly startled the boy, MK tensing up suddenly as he once again quickly glanced around the room. “Who- Who was that?!”

        Silence. That was all MK got in response, and frankly, he wasn’t very happy with that at all. “Yo... I-I said who was that-?! I-I’m the king’s f-friend-! Yeah! And if you don’t come out, I-I’m gonna have to get King Asgore-!”

        ’You know the king?

        ”Wha!” Another yelp escaped the boy, who then stumbled back before stopping and staring intensely at the entrance. Yeah. That had to be where the perpetrator was hiding; they couldn’t be hiding anywhere else in the room, right?

        With a frown, the boy then scratched his head, trying to figure out where the new person could be hiding when... wait...

        ”Wait- What?! Where did these come from- I don’t have hands!” Quickly, MK was thrown into a panic, only to begin examining himself. He not only now had hands, but his tail was much longer and was he- Was he taller?! He had no idea, but before he could think, another voice had interrupted his thought process.

        ’That’s not my body-‘ was all MK heard, the boy once again searching for this voice, and like usual, he came up with nothing. All he could do was yell questions at the voice, even if she’d beaten him to it.

        ’Who are you?!

        ”Yo- who are you?!”

        ’I asked you first.

        ”Well- I asked you second-!”

        ’I still asked you first! Besides, you’re the intruder. Now tell me who and what you are, and where’s the king?! No one comes down here except for the king!’ MK flinched as she yelled at him once again, the boy thinking about answering her question, but at the same time, he wished to know the answer to his own first.

        ’Stop that!’ He then felt his own new hand smack himself, the boy letting out a quick, “Ow!” while the voice in his head grumbled something along the lines of, ‘That hurt more than I thought it would-


        ”Yooo! You’re in my head! How’d you do that?!” Within seconds, MK has gone from being angry and confused to overall amazed, the boy then staring down at his hands as he tried to figure out how to manipulate these new limbs. However, he clearly had no handle on them, and that especially became obvious when they suddenly crossed themselves over his chest by themselves. “Hey! What gives?!”

        ’You really don’t know how to use your own arms, do you? Dummy.

        ”I’m not a dummy!”

        ’Then stop acting like one and tell me who you are! And don’t try to pry at my memories! I’m not stupid, and you’re definitely not slick!


        ’Who are you?!

        ”I’m Martie!” Frustrated, MK had decided to give in. “But everyone calls me MK! Now answer my question, you big bully!”

        ‘Whatever. I’m Lucy. Just Lucy. Now why did you absorb me? Only the King of Monsters is supposed to do that.

        ”I- I what-?!” MK then looked towards the shattered jar once again, the boy staring at it as if trying to once again figure out the location of the yellow soul. He couldn’t have absorbed it! There’s no way! All he’d done was reach out to grab it...

        ’...You didn’t mean to. Hmph. I guess I’m stuck with you now,’ Lucy grumbled, only for MK to retort with a quick, “That’s not a bad thing!”

        ’Whatever. Maybe the king can fix this... Where’s the king anyway? And why are you here?

        ”He’s in the throne room! And I’m here because he... he...”

        ’What? He what?

        Barely allowing Lucy to finish her sentence, MK suddenly launched himself out of the room, tripping over himself at first, but he’d quickly caught his balance and continued to run, running faster than he’d ever run before.

        ’Where are we going?!

        ”The king! We gotta help the king! He’s in trouble!”