Have you heard the story about two races: monsters and humans?
Well… this is partially about that story.
When a universe is subject to timeline altering and reversing,
Its boundaries begin to fade.
When that happens, it is left open to numerous other universes and multiverses.
This is the story of one such happenstance
Where the residents of one world have to cope with the lawlessness of another.
In a world that had truly become kill or be killed.
Sans let out a quiet sigh as Frisk went off to explore the underground one last time before passing through the "newly" shattered barrier. He had a distinct feeling that the barrier had been shattered before this and he knew it wouldn't stay shattered for long; his awareness of the time loop everyone was stuck in didn't help his case. However, for the sake of Papyrus and everyone else, he continued to act as if this was a momentous occasion. At the same time, he was feeling a new feeling; a feeling of dread as to what the surface will hold, like everything had shifted… unfavorably.
It didn't help that he felt a chill coming from the exit to the underground. He normally doesn't feel a "cold" chill; he's just a skeleton.
Frisk had some lingering doubts plaguing his mind as he went back to visit Asriel after he destroyed the barrier for everyone. The reason he kept resetting was because he kept trying to find a way to save Asriel, who was doomed time and time again to be left all alone in the underground and be transformed back into Flowey. It wasn't until recently, a few resets back, that he realized just how selfish it was of him to keep denying everyone's freedom just so that he could attempt to save one lost soul.
He still carried the guilt of giving in to Chara's suggestions and attempting a genocide in one timeline. At first, he reset each time he killed a monster after having doubts about it, but Chara kept egging him on, telling him, at a point where he felt stuck in a hopeless time loop in attempts to save Asriel, that he would be able to find a way to 'end' the loop if he first killed everyone in his path. It was Sans who ultimately convinced him to stop entirely, with his words of everything suddenly ending tipping Frisk off that Chara literally meant ending the loop. Many resets later, after telling Chara that he would never go through with his idea ever again, and he still feels the sins crawling on his back.
Reaching Asriel, they were able to talk about the things they normally talk about at this time, but Asirel had trailed off when he was telling Frisk to go back to their friends. "I-I mean… the surface world isn't as nice as everyone thinks, but… something suddenly feels very wrong with it."
This baffled Frisk. "What do you mean by that? I understand that humans won't be so accepting of monster initially, but I would think- "
"Frisk, it isn't about the humans on the surface. I don't know why… but I feel the surface feels… more hostile that what I saw of it when I went up there." Seeing Frisk's confused look, he shakes his head. "Just be careful out there. Don't kill and don't be killed… I want to say that, but the choice might be taken out of your hands. Not everything and everyone has a concept of mercy."
Now it was Frisk's turn to shake his head. "Why are you suddenly being so pessimistic? You're talking like the whole of the surface world has suddenly changed when I don't think that's possible."
Asriel sighed. "Anything's possible, Frisk. Still, even if I'm wrong, be careful anyways. There are plenty of Floweys out there."
He didn't say anything else, so Frisk was forced to leave, disappointed that he still hasn't found a way to save his friend. What also weighed on him was Asriel suddenly insisting that the surface was even more dangerous than before, despite not having been up there since he absorbed Chara's soul all that time ago.
While traveling through the ruins, Frisk suddenly felt an unnatural chill. He tried to summon his Reset button… but it didn't appear. An otherworldly force was preventing its appearance. "Then again… I'm not feeling totally determined right now…"
Whether they like it or not, they were now stuck in this timeline for the time being. Frisk took it as a sign that saving Asriel is beyond his power at this point and headed back towards the exit of the underground, now filled with dread.
Isis was feeling a distinct unease as the sun slowly began to set over the land. Just a few minutes' prior, she felt a shift in the world's magic and landscape, her powers as a dryad being useful for that much. This wasn't like the small disturbance that was cause by the Eye of Cthulhu's death that initially drew her to settle in her current location. It was a far bigger shift that what she would ever hope for.
She snapped out of her focus when she heard her door open and saw a familiar face: an amnesiac green-haired and eyed girl like herself wearing tungsten armor, with the helmet currently removed, and the one who defeated said Eye of Cthulhu and allowed her to move in. "Delta, what it the matter? You look pale."
Delta shook her head. "Isis, do mountains appear out of thin air normally?"
"No, they shouldn't."
"Then could you explain to me what I'm seeing westward?" The two females exited the house and saw in the distance a mountain that wasn't there before.
Isis shook her head. "Perhaps that's the cause behind the disturbance I felt earlier." Turning back to Delta she said, "But we can worry about that in just a moment, since nothing else has really change. I recall you went on another underground expedition earlier. How did it go?"
Delta snorted, feeling like the dryad was trying to avoid the elephant in the room for a moment longer. "Abysmal. Barely got further than when I did before and I only found a pittance of tin and iron." Looking back at the mountain she added, "Speaking of exploring, I should probably scout out the situation at that mountain to make sure nothing too dangerous surfaces."
Isis looked back at Delta with surprise. "You do realize you have to go through- "
"I'm aware and am willing to make the trip. The sooner we find out about this mysterious mountain, the better prepared we are for whatever else it brings." Equipping her Tendon Bow, she gives Isis a wave good-bye before running towards the mountain as fast as her Hermes Boots could let her.
Isis lets out a sigh. "I hope she doesn't get herself killed… again. So… reckless." Shaking her head, she goes back inside her house, hoping Dante didn't see her; she's already had enough of his flirting for a day.
When Frisk got back to his "new" group of friends, all of them suddenly seem unnerved. "What's wrong?"
Undyne grunted. "Nothing too severe yet. For some reason, all of us started feeling unease at going to the surface now. Even I'M unnerved… but only a little bit."
Toriel let out a sigh. "Forgive me, my child. Despite you going through everything just to break the barrier for us, we suddenly get cold feet about actually going."
Despite the bad blood currently between them, Asgore nodded. "The sight and feeling of the sun is within our grasp, yet this unease won't take its leave. Perhaps something is trying to tell us something?"
Alphys gave Asgore an odd look. "W-what makes you say th-that? Surely it's just the anticipation of finally seeing the surface for the first time."
"BUT OF COURSE," Papyrus burst in with his trademark enthusiasm. "AFTER ALL, NOTHING COULD BE BETTER THAT TO SEE EVERYONE'S HOPES AND DREAMS COME TO FRUITION!"
Sans held back a sigh. "Of course, bro. Feeling it in your bones that this will be a good time?"
"WHY OF COURSE, BROTHER! WITH OUR NEW FRIEND, FRISK, BY OUR SIDE, NOTHING CAN STOP US!"
Undyne laughed. "That's the spirit! Why was I even worried! As long as we're together, there's nothing we can't overcome!"
Frisk refrained from shaking his head. As much as he wants to share Undyne and Papyrus' enthusiasm, the fact that the monsters initially felt unease like Asriel did didn't help his case. He looked at Sans and realized that the skeleton felt the same way. Both of them nodded at each other; whatever happened would happen, no sense worrying too much about it.
"THEN WHAT ARE WE WAITING FOR?!" Everyone present headed for the exit at Papyrus' word.
When their eyes adjusted to the light, they saw the sun setting over the land, giving it a beautiful orange color. Asgore spoke the same thing he always did before: "Isn't it beautiful, every… child, what seems to be the matter?" He took notice of Frisk's horrified look and had cut himself off.
Frisk looked over the landscape, the slight orange hue not fooling him in the slightest. "This isn't the surface that I came from… not by a long shot…"
Sans had a distinct feeling why, but decided to ask for everyone else, "How so? Perhaps we're on the other side of the mountain from where you fell in."
"No, I can see the area on Mount Ebott where I fell into the underground in the first place." Waving his hand in a direction he adds, "There should be a city right there and an ocean closer than the one in in the distance."
He was beginning to see why Asriel started speaking the way he did, why everyone felt unease coming up to the surface, and why his Reset button isn't appearing.
Mount Ebott and the underground as a whole had somehow been moved to a new location… and the four distant splotches of red on the landscape looked… uninviting.
This had the effect of unnerving the group of monsters once again, even Papyrus this time. It was somewhat broken when they saw a green, gelatinous blob hopping across the nearby rocks. Everyone instantly knew it was different from the Moldsmals inhabiting the ruins. Prompted by this, Frisk did a check on it:
*Green Slime - HP 14 ATK 6 DEF 0
*The weakest strain. Hops around mindlessly all day. May hold useful items in its body.
He instantly noted that this particular slime had less HP than even he did; someone could look at it funny and it would die, which instantly worried him. Undyne shook her head at the sight. "It'd be pointless to ask that… thing about where we are; it looks as brainless as a Moldsmal."
Asgore looked at the landscape in confusion. "So, this area contains monsters that freely roam the surface. I wish I could say it's a good sign, but I feel there's more to it than that."
A fair distance away, Delta had climbed high enough to see and observe a group of monsters that were just… standing there, which was weird for her. "Most monsters can't sit still. Even if they could, they would sense me and move to attack me."
Another thing she observed is what the monsters are. She noted two skeletons, monsters she only, thus far, ever found underground near the cavern levels. It was strange to see them on the surface, even before night.
The next she observed was two big goat-like monsters, one with large horns and a regal looking cape. Delta noted that she's never seen goat monsters period, along with the other two monsters, one looking somewhat like a merfolk and the other being a large, yellow, bipetal salamander wearing a lab coat.
When she finally took notice of the human male among them, she realized that they may not be hostile monsters; most monsters she has encountered would rather spray her innards over whatever cavern she finds them in rather than be a sapient being.
When the shorter skeleton suddenly started looking around like he knew someone was watching, Delta backspaced a bit and wondered if that particular human was the only one they weren't hostile to. Perhaps they-
"EXCUSE ME, ARMORED HUMAN, BUT MAY WE ASK WHERE WE ARE?" Delta let out a high-pitched yelp and fell down the mountain a bit when the tall skeleton snuck up on her. She didn't realize he had left the group, more than likely having spotted her at some point.
The more feminine goat-monster sighed upon hearing the yelp. "Papyrus, please don't sneak up on people like that. That's a good way to make enemies."
The skeleton called papyrus responded with, "I'M SORRY, MRS. TORIEL. I JUST WANTED TO KNOW MORE ABOUT THIS LANDSCAPE SINCE HUMAN FRISK DOESN'T SEEM TO KNOW."
Delta sighed as she recovered from her scare and fall. "At least you only scared me with a question and not a bone through the spine."
This made some of the other monster's grimace, with the short skeleton saying, "Sheesh, dark much? Mind you, I'm curious about how long you were there watching us."
"I was trying to gauge if you were hostile monsters, which was proven false when I noticed your human companion there with you." Delta motions at Frisk. "Still, can you blame me when your mountain appears out of thin air for no reason?"
The merfolk monster grunted. "Guess that confirms Frisk's concerns. Still, you never answered Papyrus' question."
Letting out a sigh, she went up to the ledge the monsters were standing next to. "Guess you guys are as confused as I am. Sadly, you guys got the massively short end of the stick if this was purely by chance." She waves her hand in the direction of the landscape. "Welcome to Terraria, and you may not like it, period."
The start of this story is inspired by BadDRUMMERboy15's Undertale crossover called TerminaTale. Also, while it may be already apparent, gore and violence will be present in this story.