Well, flinging is always fun.

Whee?

Wheeeee~

Or, in more precise terms, the—apparently it's called an Aerial Faith Plate—pushes her off the ground the moment both her feet are on it, with exactly the right amount of force to cause her to arc perfectly and land neatly on the blue target on the other side.

So clearly the thing to do here is to drop a cube and then whee herself back over so she can catch it in midair, right?

Correct!

Whee!

And then whee again back to the second platform so she can put the cube on the button!

"Here's an interesting fact: you're not breathing real air. It's too expensive to pump this far down. We just take carbon dioxide out of a room, freshen it up a little, and pump it back in. So you'll be breathing the same room full of air for the rest of your life. I thought that was interesting."

"You have a bizarre sense of humour."

"I'm sure a human like you wouldn't understand."

She laughs a little.

Elevator!

"Let's see what the next test is. Oh. Advanced Aerial Faith Plates. Well. Have fun soaring through the air without a care in the world. I have to go to the wing that was made entirely of glass and pick up fifteen acres of broken glass. By myself."

"Sounds tedious."

"Oh, yes. Extremely."

The next test chamber is mostly a vast gaping chasm filled with water. There are islands with the Aerial Faith Plates on them in the water, and across the room is the exit door, and a small button standing on a pillar. The exit door is connected to something but that something is not quite visible from where Sable's standing.

The Faith Plates—including the one Sable can reach—are pointed, apparently, at each other and eventually at the exit door, except there is one pointed to an alcove on a wall attached to the back of which are two portalable wall segments angled upwards.

Hmm.

They seem like they line up right, if she drops portals on those two wall segments... well, only one way to find out. Whee!

It works. Whee~

She reaches the place where the exit is, and from there she can see that the thing connected to the exit is a big button, with a portalable ceiling above it. The pedestal button she can press has cube dropper symbols, and conveniently there is a cube dropper above the first of the Faith Plates.

Goodness. Does that mean the cube gets to go whee?

—no, actually! The cube dropper emits some sparks and then a bunch of junk, including a couple of balls and a chair and a defective turret and a radio, spills out and starts being thrown around.

"Oh, sorry! I'm still cleaning out the test chambers. So sometimes there's still trash in them. Standing around. Smelling, and being useless. Try to avoid the garbage hurtling towards you."

She giggles. She stands out of the way of the garbage.

It flies past her and into the toxic water behind her. "Press the button again."

Button!

Cube!

And can she perchance redirect said cube to the place where it needs to go?

Well there is a conveniently portalable ceiling directly above the cube button...

Boop?

Flying cube goes through one portal and out the other and lands neatly on the button and the door opens.

"Remember before when I was talking about smelly garbage standing around being useless? That was a metaphor. I was actually talking about you. And I'm sorry. You didn't react at the time, so I was worried it sailed right over your head. Which would have made this apology seem insane. That's why I had to call you garbage a second time just now."

"I did too react," she points out, traipsing merrily out of the puzzle chamber. "I laughed!"