Undertie #6

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UNDERTIE

Chapter 6: The Sea Beneath the Sea

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They sailed north.

Not because it made sense. Not because the map told them to.

Because the fog had teeth now.

The journal fragment from Gaster’s ship whispered of a location—coordinates scratched faintly in the corner of the page. "47 North, 0 Light." The numbers made no sense. There was no land that far north.

But the wind pulled them there anyway.

Even Ralsei said it felt like something was calling.

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Noelle dreamed in frost and numbers.

She saw ships drifting upside down in the sky. A spiral staircase carved from coral. A mirror sea that showed another ship—their ship—on the underside of the ocean, sailing upside-down like a reflection.

When she woke, her hands were covered in ink.

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Day four. The compass spun like a coin on a tabletop. They passed glaciers shaped like teeth, icebergs that whispered. The water turned black. Not navy. Not deep. Just black. Colorless. Soundless. Wrong.

> “This place feels like it shouldn’t exist,” Ralsei said.

> “Maybe it doesn’t,” Kris muttered.

The parrot had stopped speaking.

Even Susie was quiet.

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They found the tower on the fifth day.

It rose from the ocean like a broken bone—spiraled and dead, with no entrance, no windows, and no reflection in the water.

They dropped anchor.

And then the sea began to fall.

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It didn’t make sense.

The water just… receded. In a circle. Like a drain had opened in the heart of the ocean.

And below them, slowly revealed, was a city.

An entire city, built of coral and glass and rusted ships, forming spires and bridges and statues of screaming faces. It had been buried under the waves for centuries.

Now it returned.

They climbed down.

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The city had no name.

It had no sound either.

No wind. No waves. No heartbeat.

Their footsteps echoed off coral streets. Fish swam through the air like birds. Barnacles grew on floating doors.

Kris touched a wall.

> “It’s warm.”

Frisk found a doorway with ancient carvings. Ralsei began translating:

> “The One Who Watches.

The Mouth Between Moments.

The Voice With No Face.

Gaster.”

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That night, they camped in a half-submerged temple. Noelle kept watch with Susie.

She tried not to stare, but Susie’s arm was bleeding again.

> “Why don’t you let me—”

> “I can handle it.”

> “I know. But you don’t have to.”

Silence.

Then, awkwardly, Susie said, “You’re not bad at this. Sea stuff.”

Noelle beamed. “Really?! I mean—I try. I read books. Well, I mostly trip over things. But I’m learning! You’re—um. You’re really cool. And scary. But mostly cool.”

Susie blinked.

> “Do you ever stop talking?”

> “No. Sorry.”

> “...Good.”

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The next day, Gaster spoke.

Not with a voice. Not from a mouth. But from every wall, every puddle, every reflection.

> “YOU HAVE WALKED TOO FAR TO TURN BACK.”

> “THE SEA HAS A MEMORY. YOU CANNOT KILL A WHISPER.”

They ran.

Statues turned to look at them. Ralsei’s magic fizzled. Kris covered Frisk’s ears.

Susie dragged Noelle down a spiral staircase as the walls bent around them like the sea itself was breathing.

They burst into a cavern of anchors and bones.

And there, at the center, stood a shape:

Cloaked in static. Wearing nothing. Staring with sockets made of spirals.

> “I AM THE FIRST CAPTAIN.”

> “I SAILED BEFORE STARS.”

> “I REMEMBER WHAT THE KING FORGOT.”

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The battle was not physical.

Gaster attacked them with memories.

Susie found herself alone on a burning dock—her childhood home behind her, and a ship she didn’t recognize in the distance, sailing away with her past.

Noelle stood in the frozen court, her mother pointing at her with cold eyes. “Why did you leave us? Why weren’t you enough?”

Frisk walked through empty alleys where no one recognized them. Even Kris looked away.

Kris stood in front of a mirror and saw no one.

Ralsei was the only one who didn’t move.

He stepped forward.

And he said: “We are real.”

The city shattered like glass.

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They awoke on the ship.

No memory of climbing back.

The sea was blue again. The fog gone. The compass steady.

Only one thing had changed.

Kris opened their hand.

Inside was a broken spiral medallion, warm to the touch. Gaster’s mark.

> “One down,” they whispered.

> “Two to go.”

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END OF CHAPTER 6: The Sea Beneath the Sea

—Gaster Saga, Part I

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