They can be very careful. The later half of their lives was on an island, they can go around slippery rocks.

If only, they could put on some rails or anything, but that would ruin the whole secret lair thing.

Hm maybe they could do a sort of natural-looking rock rail? At least under the falls where it wouldn't be so visible. For now they're safe enough if they hug the wall. 

The cavern really is as massive as Uncle Remi had suggested when he mentioned it the year before, an enormous mist-filled chamber lit only by the watery light streaming in from the entrance, growing darker at the far reaches. The water deeper inside is pitch black, the stalactites dotting the ceiling are nearly indistinguishable from the surrounding darkness, and one can only just see the solid area the path leads to looming out over the lake in the misty dimness, along with the bare impression of a building, partly completed.

The building's main supporting structure is done, but hard to see in this light. It's meant to evoke the style of a small castle, with square stones for the walls. The cavern is not actually castle-sized big, but once complete the structure will have two stores including two cylindrical "towers" with domes. One dome for the constellations of Amenta's northern sky and the other for this planet's northern sky, each with glowing crystals for the stars. One will be a reading nook. They haven't decided on the use for the other.

But not yet, at the moment it has the bare necessities of enough walls for two rooms - a living room and a bedroom - plus a bathroom.

Tobir heads towards these, looking between the other two as they walk, "What are we working on today?" He asks, raising his voice just enough to be heard over the echoing roar of the waterfall. 

"I wanted to raise all the walls on the first floor this high," he raises his hand to around waist level, "because of the different texture. And make the left-ward room by the end of the week. But I think you guys should focus on make the inner lights. I talked with Gabe Pillar, and he thinks that my idea to make the structure glow would be pretty but might make it hard to sleep, so he advised to put some lights beforehand to see if can get accustomed to them."

"He makes a good point. Okay, we can do that!"

Light making! For an hour or so, anyway, as long as he can keep his focus on it. He keeps getting distracted by the thought of how close he is to making an empowered crystal. After a bit he takes a break, settling down in the partly-completed living room, lights flickering around him like stars in the night sky, to focus on that for a bit instead. 

He swears it's been flickering with colour all week. Red, he thinks, though it can be hard to tell. A deep red, streaked internally with black so you can only see it from the right angle...

He blinks down at the crystal attached to his arm. His face lights up, and he leaps to his feet.

"Hah!" He cheers, "Heri! Kenta! I did it!"

Heri runs over to hug him. "You did it!"

Kenta joins the hug in a moment. "He did. You did! What does it do?"

Hugs! 

He squints down at it, "I... it's..." He lifts his arm and reaches out... 

A violet-tinted distortion forms in the air in front of him, slowly widening to show an outside view of the building they're in. 

"...Portals," he says.

"Portals."

"Portals." Kenta repeats, mostly for the three beat.

And then when it sinks in. "Portals! You got portals!"

"I got portals!" He breathes again, staring at it some more, and then he blinks, hard, "I need to-" he reaches out with the magic again, trying to reach a bit farther, and another portal opens up next to the first, widening to reveal the settlement on the main island.

He starts to grin, "I can open them between islands. I think I can go farther than that, too - guys-!" He untangles himself from them a bit, motioning up at the sky (well, the ceiling of the cave), "This might be a way to get everyone off this planet!"

"You got planets!" Heri stares at his brother in wonder. "We should tell Remi."

"We should tell everyone!"

"Planets, for this world, and for..." he laughs, "We should! First, though, here-" he manipulates the little crystal until he has two slivers of it, which he pulls off and hands one of to each of them, "The more people working on it, the better, right?" 

"True!" Heri says accepting the crystal.

He takes the crystal... how does it work? Can he aim for Remi?

Kenta takes his and tries to reach his home at the main island.

Kenta can absolutely aim for his home on the island! It doesn't look like Heri can aim for a person, though. He could try aiming for the lab where Remi was last they knew?

Heri tries that.

Kenta's portal causes people to peer through. "What?"

That works. Remi glances up from his work and blinks at the portal, before shooting to his feet. "Heri?!"