A Sentinel starts wandering in her general direction.

Second Naomi reaches her destination, curls up, and starts gestating a Tunneler.

First Naomi decides to hold off on laying this egg. The approaching Sentinel is far enough away from her hut that she's pretty sure it couldn't hear her from there, but she doesn't know how fast they can move, and she doesn't want to find out what it would do if it found her while she was still screaming. She makes sure there's no liquid Clay visible aboveground, and waits.

The Sentinel keeps wandering in her general direction for a while, then stops wandering and makes a beeline for her.

—tunnel time bye.

With both of her belowground, it's much harder to distract herself from the traumatic associations. She collapses her hut and the tunnels immediately beneath it, sucking everything deeper until there's thirty feet of dirt between the surface and the first hint of Clay; her suitcase, wrapped in a hasty shell of hardened Clay, follows her original body as she zooms southwest along the deepest tunnels in the network. And if she's whimpering quietly the whole time, well, there's nobody else around to hear it.

The Sentinel finds the point where she disappeared and starts digging downward.

There's plenty of innocent dirt there, along with a few traces of hardened Clay; the liquid stuff is receding into the ground faster than the Sentinel can dig for it, and Naomi is five hundred feet below the surface and speeding away as fast as her slime-coated tunnels can take her.

The Sentinel eventually gives up and leaves.

Well, now in the place where her hut used to be there's a lot of empty collapsed tunnels that make kind of an ugly hole in her Clay network, but on the plus side, she wasn't just murdered by a Sentinel. Call it a win.

Also, apparently the lowest layer of the network is deep enough underground that Sentinels can't see her down there. She adjusts her tunneling strategy accordingly, and sends a few Tunnelers north to see if they can cross the border safely as long as they do it from far enough down.

Her original body arrives in a Tunneler-carved cave, not far from the bottom of Lake Champlain. No one's going to hear her scream down here; she lays her egg, hatches baby Third Naomi, and starts feeding her Clay. Meanwhile, Second Naomi keeps hatching Tunnelers to expand the network.

A mutant enters her range. Then another, then another--there are a lot of them, moving as a group.

Oh boy.

...all right, where are they and where's her closest Tunneler, can she open up a tunnel nearby?

A little ways away, yeah.

Up goes a Tunneler.

The mutants freak out slightly when the thing appears!

Yeah that's fair. This is one of the oldest ones; the tunnel it makes is big enough for two people to crawl through it side by side. Unfortunately that means that it's a giant scaly worm-thing whose front end is mostly composed of big sharp rock-chewing teeth and it's five feet in diameter at that point. She has it close its mouth and attempt to look contrite while she rearranges the Clay to retract it.

Then the Tunneler slurps back down its slime-lined tunnel, and half a minute later, a very wet raccoon pops out and starts beckoning to the mutants with humanlike sweeps of its little arm.

(Meanwhile, she leaves Third Naomi curled up at the southernmost point of her range making Tunnelers one after another, and has First Naomi and the slightly bedraggled suitcase start heading north. She's pretty sure a couple of those Tunnelers have made it past the border unharmed, and she would like at least one of her to follow them. Second Naomi starts gestating another clone.)

The mutants confer, and then a subset of them enter the tunnel.

It's dark in there, and slimy. But the slime doesn't slip under their feet or linger on their hands when they touch it. Very well-behaved, that slime.

The tunnel angles downward. When it forks, Naomi blocks the same-level fork with a wall of living Clay, to direct the mutants down the fork that leads to the next level down.

First Naomi and her suitcase are getting close to the border. Third Naomi is the one nearest the mutants. She sighs, abandons her latest Tunneler spawn, and slime-slides up the tunnels to meet them; she can't think of a way to get a raccoon to mime 'please ride the sixty-mile-an-hour underground waterslide to Canada', and she doesn't want to alarm them by snatching them away without warning, so this is going to require actual human words.

The mutants proceed cautiously down the tunnel.

And a naked girl covered in slime comes rocketing up the tunnel toward them.

"Hi," she says, stopping about ten feet away. "Sorry about the mess. I can get you all to Canada but you have to go waterslide-style and let the tunnel do the work unless you want to walk all fifty-odd miles of it five hundred feet underground—that's how low you have to be before the Sentinels can't see you anymore. Well, they can't see me that far down. I don't know if it's different when you're actually a mutant."

The one in front steps forward. "It would certainly be a good thing to have a route out. Is this a one-time or ongoing offer?"

"...I hadn't realized you might want to delay taking it. Uh, the offer's open indefinitely, unless you all get murdered before you make it back into the tunnels, in which case sucks to be you?"

"We'll certainly want to evacuate the children immediately, but we have the ability to fight Sentinels and win, and the resources to find other mutants with less ability to get out on their own."

"Oh, I've found the big boys, have I. Well. I'm digging more tunnels as fast as I can; keep the gross raccoon, I can use it to hear you if you're in range of my network. Who's going to Canada on this trip? Send 'em down. And if you don't have any more questions, I'd really better get back to work."

"Alright."

"Bye!", she says, and zooms away on a splash of goo.

(Second finishes feeding Fourth, and sends her out into the network while Tunnelers dig her a cave near the middle. Third starts another clone on her way to her resting place. The western Tunnelers are making headway under the lake, and First in the north has just about decided she's far enough past the border to risk coming up for a look around.)

The mutants return to the surface, confer for a little while, and then a group of them consisting mostly of children but with a few adults along, presumably to mind them. The children seem delighted by the slimy tunnels, and have to be dissuaded from attempting to do unwise enthusiastic things.