Alphys could barely control the shaking of her hands as she dialed Undyne's number.

After five excruciating seconds, she picked up.

"Hiya! Are you all set up?"

"Um. Yes?"

"Great! I'm just about ready over here. I've got all the test subjects lined up."

"They are volunteers, right?"

"Of course! When I ask, anybody volunteers."

"That's… um…"

"What?"

"N-never mind."

After an uncomfortable pause, Undyne said, "You sound like you don't want to do this."

"Well. I-it's kind of dumb, isn't it? It doesn't seem like it should work."

"What? No! You came up with something I can understand! That's great! It doesn't matter how sciencey it sounds. And what's the harm in trying? What's the worst thing that could happen?"

"I, I think you might be surprised -"

"Nonsense! Come on, let's get started!"

"Alright then. Let me just…"

She put the phone on the ground and started the camera.

"Clown Car Protocol. Experiment number one."

She took a deep breath.

"F-for the record, I thought another name would be better, but -"

"It's a GREAT name!" Undyne yelled through the phone.

Alphys picked up the soul container and unscrewed the lid.

The purple glow was mesmerizing.

"Everything is in position. Because maintaining communication might be impossible, Undyne is to attempt transmission fifteen minutes from now. I'm about to absorb the human soul."

It was funny. She had planned out the whole experiment, but until now, she hadn't thought about how this part would work.

She decided to just reach into the jar and see what happened.

As soon as she touched the soul, it stuck to her fingers and started creeping up her arm and seeping through her skin.

Her mind was flooded with emotions she'd never felt before.

She started gasping, and tears came to her eyes. She fell over, and vaguely felt something breaking.

When she could stand again, everything looked different. No longer wearing glasses was probably part of it, but that didn't explain the additional 90 degrees in her field of view, or the new colors.

Too bad she didn't bring a mirror.

Picking up the box and carrying it to the barrier was effortless, which was almost a shame, after all the exercise Undyne made her do to prepare.

Pushing through the barrier was a bit harder. But with a lot of sparks and a weird whistling sound she made it through.

She put down the box, lay on the ground, and let the power drain out of her. A purple vapor left her body and spiraled up into the sky.

The first thing she noticed as her body reverted to its natural state was the chill. She should have expected it, high up on a mountain, late in the year, but it still came as a surprise.

Then she realized she left the camera inside the cave.

She decided to do nothing and wait it out.

The lid was pushed open. A kid's head popped out. "Yoooo! It's really the surface! Awesome!"

They stepped out of the box to make room for Undyne. "I knew you could do it, you nerd!"

She made way for another, then another, and another - they kept coming. Everyone was cheering.

Alphys was still lying on the ground, smiling now. She tried to focus on the box, inches away from her face.

It was covered in scorch marks, but the text on the sign affixed to it was still clearly readable:

This is a box.

You can put an item inside or take an item out.

The same box will appear later, so don't worry about coming back.

Sincerely, a box lover.