The waterway passages were long, winding, and seemed to carry Undyne and her reluctant passenger in all possible directions, the massive channels occasionally opening into larger reservoirs, only for the sweeping currents to carry the two into more waterways. From the identical blue-green stonework that surrounded them on all sides, it was near-impossible to tell where they had been and where they were going. Throughout the whole journey, Undyne's white-knuckle grip on Kazuma's arm never loosened.

Finally, Kazuma spoke up. "Hey, Undyne?"

"What's up?" she responded, not even bothering to look back. "Need another hit of oxygen?"

"What!? No!" said Kazuma. "I was just wondering; do you know where we're headed?"

"Not exactly, no."

"How reassuring," Kazuma remarked.

"Do you have any better directions, Mr. Smart Guy?" said Undyne.

"…No."

"Then complaining about it isn't going to help," Undyne retorted. "We'll find our way to the top of this Island, even if we have to explore every last inch of these waterways."

Kazuma sighed. Just before he could make another sarcastic comment, he noticed something in the waterway ahead, just above his peripheral vision. Just as the current dipped and headed downward into a lower chamber, the top of the waterway opened into a small alcove with a pocket of air. At the edge of the alcove was a plain metal door embedded in the cavern wall.

"Hey, do you see that?" said Kazuma.

"Must be some kind of maintenance room," Undyne replied. "We should probably check it out."

Before long the two had made it out of the water and into the alcove, though Undyne had a significantly easier time adjusting to the sudden change in environment than Kazuma did.

To say that he felt sick was an understatement. It was nearly impossible for Kazuma to hear anything over the sound of his retching and gagging. He tilted and staggered, his head still feeling like it was being pulled forcefully through the water even as he struggled to walk upright.

Undyne had given him plenty of distance, which turned out to be a good idea when the water remaining in his lungs was forcefully ejected through his mouth. It felt like vomiting, only somehow even more unpleasant.

Undyne wrinkled her nose at the sight. "Jeez!"

"H-hey, don't blame me!" Kazuma gasped. "My body's not built for breathing underwater!"

"Maybe we should go inside and take a rest for a bit," Undyne replied. "Not for too long, just… enough to get yourself back together."

"Yeah, I think I probably need that."

After pausing to catch his breath, Undyne had led the watersick human out of the alcove and through the door beyond.

The interior of the building was small, and sparsely decorated. There were a pair of bookshelves just to the right of the door just before the wall, and on the opposite wall was a single bed, stationed next to a desk and chair with an antiquated PC. From the cracked, unresponsive and the thick layer of dust, it appeared that the computer had not been used in a long time.

Most notably, however, was a large hole opposite the door that they had entered from. The space beyond its threshold was grey and rocky, but the meager light from the cabin's weak fluorescent lamps failed to show more than a few feet beyond the entrance. The opening in the wall looked like it had been made only recently, and inwardly Undyne wondered if it had been caused by the Island's near-fall during the Sakamoto family's last expedition.

As Undyne sat glumly on the side of the bed, Kazuma had stood by the side of the door, removing his coat to wring out as much water as he could. He was too embarrassed to remove any more of his clothes, even though Undyne had told him that she wouldn't want to look at his scrawny body anyway.

She had tried not to think about how much time they were wasting as they were stopping to rest. In the back of her mind, Undyne knew that anything could have happened to her friends already. She knew that some of them could even be dead.

It was a horrible thought, one that she tried to push out of her head as soon as it made itself known, yet no matter how hard she tried to ignore it, it lingered. Worse yet was the strange feeling of sorrow that swelled within her whenever the thought came to attention. Not merely an ordinary sorrow, but a familiar one. It felt like… like…

…like her friends had already died before. Even though that was impossible, it felt true. It was almost as vivid as any memory that she could recall.

Undyne shook her head violently, trying to shake off the ever-increasing worry that she was going crazy. She slowly picked herself off of the bedside, now dampened by her still-wet body, hoping that whoever lived in the cabin wouldn't mind the indentation in the bed frame left by her heavy armor. Out of boredom, she walked over to one of the bookshelves, while reaching back and wringing the remaining water out of her ponytail.

Most of the books were old covered in dust, but one of them immediately grabbed her attention. Though its leather spine was much less worn than the others, it too was covered in dust as well… but it was a dust Undyne immediately recognized as a different kind.

Feeling her stomach clench and her heartbeat quicken, she reached out towards the book, her skin crawling as her fingers came into contact with its exterior. She winced as she pulled it out of the space where it rested, wiping off the thin layer of grisly soot.

The book was unremarkable, a simple tome bound in plain brown leather. There wasn't even a title or author to be seen. Flipping through it revealed most of the pages to be blank, though she soon realized that there were a sparse few pages near the beginning that had been filled. Her curiosity now overwhelming her revulsion, she squinted her eye, straining to make out the words in the cabin's dim light.

January 12th, 211X

I keep finding myself coming back to this place. The place where I saw her eyes open again. I still remember it vividly, seeing the smile on her face when she looked at me and saw that I was alive. I don't think I've ever seen her happier than that day.

I still have nightmares about it. The day that I nearly lost her. In my dreams, I see a world where she had died in the Core's chamber, left behind with no way back. A world where she had never sought to destroy Ballos, where I had never found her on that hellish path. I see in my dreams the Island crashing to the ground, and everything that once lived there dying with it.

The dream always ends the same way, with a wish to bring her back. Every ounce of willpower I possess pushing against destiny itself. Every part of me screaming, wanting nothing more than to start over, to find a way that I could have saved her.

And then I awake, in a world where she had always lived.

I don't know what it means. I don't know why the dream feels so real. Sometimes it's so convincing that I wonder if this world is the dream, and the world where she'd died is reality.

Maybe that's why I keep coming back here. Maybe that's why I felt the need to write this. Maybe I just need to remind myself that she survived.

February 27th, 211X

Spending time with her no longer brings me the satisfaction that it used to. Even before I met her, I was vaguely aware that I had a purpose, but it wasn't until I had fought by her side that I felt my existence really MEANT something.

I had given everything for her. I fought knowing that it was for her sake. Together we'd faced unimaginable odds and defeated everyone who stood in our way. But all of that is gone now that everything is peaceful.

I don't know what to do with myself now. Every day I feel more and more deprived. It's difficult to describe, like a creeping numbness from within.

I've started going on regular hunts, hoping to feel something again. So far, it hasn't helped any. As far as I know, it could be a useless exercise.

…but I just don't know what else I CAN do.

March 15th, 211X

The Blade has abandoned me. It used to lend its power to me easily, but over the past month I've felt that power fade away. Now that power is gone, leaving it little more than a large cutting knife.

Maybe it's for the best that I leave it behind. I've already fulfilled the promise I made, and a weapon that won't serve me is useless.

I probably won't bother coming back here again, or writing in this journal. I can't let myself be distracted from my mission. The hunt is my true purpose now.

The rest of the pages were blank, as sure as the writer had promised. Undyne closed the book forcefully and placed it back on the shelf, trying not to shiver at the chill that had suddenly run down her spine.

Whoever wrote this book is still out there, she realized. As if I don't have enough to worry about.

Before she could continue that train of thought, she noticed a glint of steel in the space between the bookshelves. Crouching down, she peered her eye between the crack and saw the edge of a sword. It almost seemed to glow on its own, its metallic surface gleaming more brightly in the cabin than the dull fluorescent lamps would seem to allow.

Undyne reached her hand into the crack, carefully probing her fingers up the weapon's surface, until she grasped the handle. Pulling it out carefully, she was able to look at the sword clearly.

It was a simple one-handed longsword with an unremarkable design, though she could tell that the weapon was forged from finely-crafted metal. Its otherwise plain appearance was made distinguishable with a large green ribbon that was tied onto the grip, just below the cross-guard.

As she held the sword up in front of her, she felt… something. It was difficult to describe, like a gentle warmth, but there was also something else. Something that resonated with every part of her being, flowing inwards into her body, until it penetrated her very soul.

The Blade was not merely a weapon, she realized. The Blade was something altogether greater than that. But what that was, she did not yet know.

Shifting her grip on the weapon, she stood back and gave a practice swing. Then a few more. Thrusting, stabbing, slashing, she danced with the Blade, carrying a grace she could not have possibly anticipated. The spear was the only weapon that she'd ever trained with, and yet she could make use of the Blade effortlessly. It didn't even feel like a weapon at all, but simply another part of her own body.

Kazuma, not fully paying attention, approached Undyne as he finally squeezed the last bit of moisture out of his coat.

"Hey Undyne, I think I'm feeling just about ready to – gyah!"

He let out a startled cry as the Blade came just inches away from his face, slicing the rolled-up jacket he was holding in his hands in two. He stumbled backwards and fell onto his backside.

"Ngah!" Undyne cried out. "Oh my God! Kazuma, are you okay!? I'm so sorry!"

Kazuma's body trembled as he pointed a shaking hand at the sword. "Y-you put that thing away before you kill me with it!"

"I-it was an accident, I swear! I didn't mean it!"

In a panic Undyne reached forward to help Kazuma to his feet, only to freeze in her tracks. The sword that had once been in her hands was gone. It had disappeared as soon as she had thought about putting it back where she had found it.

Judging by the look on his face, Kazuma was equally shocked. Undyne stood back, and held her hand at arm's length in front of her. With a single thought, the Blade materialized in her grip once more in a flash of light. With another, it disappeared once more. She repeated the process several times, calling the sword up and dismissing it as easily as she would summon one of her own spears.

"Okay, now I'm starting to get a little bit freaked out here…"

"You're freaked out!? You nearly cut my face open!"

"L-look, it's going to be fine, alright?" said Undyne. "I… I don't think this Blade will come unless I call it… somehow. But I promise I won't hurt you, alright?"

Kazuma exhaled deeply, letting the tension in his body deflate. "…Yeah, I know. Not intentionally. Just… be careful with that, alright?"

"I will," said Undyne. "You need a hand up?"

"No, it's fine," said Kazuma. He picked himself up onto his feet, and wiped dusted off his shirt, a garment of striking teal-and-red plaid. "I'm going to miss that lab coat, though."

Undyne gave a large, toothy grin. "Pshaw, that old thing? Alphys has those by the dozens! If we make it out of this alive, I'll get you one with no problem!"

"Yeah, thanks," Kazuma couldn't help but reply with a smile of his own. "So, uh… what now?"

"Well," said Undyne, "I was thinking about going through that tunnel over there."

Kazuma glanced over to where Undyne was looking, towards the massive hole in the cabin wall that led deeper into the Island's interior. "You're joking."

"Would you prefer we go back to going around in circles?" said Undyne. "You know, in the water?"

Kazuma glanced back at the cave, then back to Undyne. "…Right. Tunnel it is, then."