Look, Creation is out of its depth -- arguably it shouldn't even understand your concept of 'natural atoms' in the first place -- and is kicking this one to their mutually containing, higher magical multiverse.

It works!

Estha's next prayers are due about four hours after sunset. Merrin would use the intervening time to get some sleep, except that she just got a Heal again and is, again, not even slightly tired. She'll do some more work on the cave-mapping. 

(The next tidal bore is due at 62:00, three hours after Estha finishes praying for spells – and in the middle of the night, though the moon will be in the sky and nearly full and they can both have headlamps – so they've got some time to iterate on their plan. Though not, like, a ton of time. Any new craft projects will have to be ones Merrin can accomplish reasonably quickly with her existing gear.) 

Following some mutual discussion of the possibilities of improvised technology -- objects you could maybe even build in Golarion, come to think on it, except that Golarion never quite imagined these objects, somehow -- Esta, in his next prayers, asks for Air Walk.

So the thing is.

Merrin is an exceptionally skilled swimmer. She did a lot of swimming as a child, and then she spent the last few years in dath ilan working for Exception Handling, training with her highly optimized aquatic power armor, perhaps with some background subtext from an inside joke that will apparently never die and that becomes funnier the more that Merrin appears to have superhuman abilities as soon as you put her in water.

She's done a ton of hostile-water-conditions training, and then she spent six planetary months here, getting more and more comfortable with riding the violent tides in and out to sea, and she knows the channel pretty well at this point, has a sense of where the rocks are, and she's pretty confident in her ability to navigate the wave in a controlled manner.

(They discussed Estha getting a version of the spell that would cover both of them, and riding along behind a floating buoy, but that would not be controlled and Merrin did not thing she could actually make a floating buoy that would survive a few violent collisions with rocks and still, like, float.)

So this is not, actually, quite as incredibly stupid an idea as it looks. 

Stupid? It’s amazing! This is sooooooo cool and Merrin is soooooo cool.

Merrin is not used to swimming with a rope harnessing a floating person on roller skates to her back.

It turns out that this substantially affects her maneuverability.

OW SHE DID NOT DODGE THAT ROCK IN TIME

She’s still conscious and mobile, kind of - she did manage not to collide with a rock headfirst, she took the impact on her shoulder - but it was violent enough that it seems to have damaged something in her suit electronics, which are now distractingly beeping alarms at her, and she’s pretty disoriented and somewhat disadvantaged at keeping enough clearance from the next set of obstacles.

OW

OW THAT WAS WORSE

- they’re actually past the worst part now, the current is slowing and they’re in a section with fewer rocks to hit and by the time they get to the next rocky bit the current will have attenuated even more than this, but Merrin is, uh, pretty sure she has a broken arm and probably some broken ribs, which has never actually happened to her before so it’s possible she’s just being an unexpected wimp about some bruises but she is not really feeling like she’s sure she can swim and navigate until Estha’s Locate Object runs out…

Esta is paying some occasional attention to Merrin, as well as to his surroundings and above all to staying upright.  Thankfully Locate Object does not require concentration.

And now he's confused, because Merrin seems visibly to be swimming worse, as if injured; and that level of impact should not have done that much damage to Mariona, let alone to Mariona in armor.

But his {comms link} is conveying a sound, probably from Merrin's armor, that sounds like Dark Tapestry artifacts sound when they are unhappy.

He'll wait until Merrin is not visibly engaged in any complex maneuvers, and then yell over the comms link, "Status?"

OW OW OW OW oh wait is someone asking her something OW oh right that's Estha and she should probably, like, explain, that she's injured -

- did she break the oxygen connection on that second impact or is it just the broken ribs making it feel like she can't actually get enough air to speak - this is so embarrassing but embarrassment is not even slightly a reason to try to conceal that she's injured and in fact the thought of doing that does not cross Merrin's mind. 

"Injured," she manages to force out; she's really hoping the comms link is still working in both directions. "Electronics damaged.”

She does not sound incredibly okay. (By the standards of Cheliax, she’ll probably come across as sounding even more badly injured than she in fact is.)

"Still mission-capable?"

Merrin is at this point not thinking incredibly clearly, and is - without meaning to or being consciously aware that she’s doing so - going to implicitly update from this even being a question that she must not be as injured as she thought, if Estha thinks they can keep going, and that it’s reasonable to defer to him on that.

(She will be EVEN MORE EMBARRASSED to realize this later, but right now pretty much all of her concentration is going toward things like “not screaming” and “keeping her body at an angle in the water where she can mostly use her legs and her unbroken or at least less-broken arm.)

“Impaired maneuverability but can still swim,” she manages. “Should - probably abort - if I hit anything else -“

And then she will focus all of her attention for trying not to do that for as long as possible.

…Which is going to be about thirty seconds, because here comes the next rocky section, and Merrin’s reaction times are very much not at their best.

She’s not actually unconscious - she did manage to tuck in her head before impact - but she is not going to be especially able to say any coherent words over the comms link about her ability to keep going.

Esta is so incredibly familiar -- you would not believe how familiar Esta is -- with subordinates pretending like they did not totally get in over their heads, and are not in all that much trouble, and don't need to fail the mission.

When Mariona does it, it's not for quite exactly the same reasons as usual.  But still, this is one of the most recognizable things he's seen her do since her brain got eaten by the Dark Tapestry.

He hauls himself down the cable and grabs Merrin, quite hard actually, because this Is Not a good time for his grasp to slip.

Word of Recall.

...He can't actually Heal her without some exposed skin, though, come to think.  Does her armor offer that?

It does not!!!

If he gives her a couple of rounds, Merrin will realize where she is and that it's not the river, and manage to put together that she's injured and probably Estha needs to do a healing spell and those are touch-range. 

She tries to use the voice-activated interface to unseal the suit helmet automatically, since that's the simplest and fastest way to expose any of her skin.

Nothing happens, because there is in fact quite a lot of damage to the suit electronics. 

She'll make an abortive attempt to lift her hand and do it via the wrist console. ....Yeah no not happening, she avoided a severe head injury by tucking her chin in and shielding her head with her arms but that means she took the impact directly on her elbows and forearms, and OW. Come to think of it, she's not sure the wrist console itself is still working, the screen seems to have gone dark...

Possibly some components of this plan were not entirely thought through. For example, Merrin has not taken the time to show Estha how any of the external controls on her suit work, since she did not think ahead to the in-hindsight-obvious possibility that she might break both the electronic voice-activated controls AND HER ARMS. 

Merrin is REALLY QUITE MOTIVATED to be in less pain than this, and will try, through gritted teeth, to instruct Estha on what button to press to get the helmet unsealed manually. At least the radio comms link is somehow still working and they can hear each other fine. 

Do what to what, now?  Does he look like he has skill ranks in this?

He will nonetheless try to follow instructions, and nothing will happen.

...Esta does not know, and should maybe have asked, how to operate the technology that Merrin used to cut Esta out of his own armor.  Well, at least now Esta will have an excuse to ask her about that, just in case, for next time, without that seeming suspicious of him.

Merrin continues to be pretty disoriented, and has no idea whether her explanation is failing to result in the helmet being open (and her getting HEALING MAGIC about her BROKEN BONES which it turns out are REALLY DISTRACTING) because she's explaining terribly and Estha doesn't know what she means, or because he still has far less basic familiarity with technology than a dath ilani four-year-old - Merrin is pretty sure she could talk a dath ilani four-year-old through the manual external controls, but they do have the advantage of, like, video games -

- oh, or it's also possible that those controls are also broken, or that the incredibly tough composite material is bent and the helmet faceplate is actually physically stuck in the closed position, in which case maybe he'll have better luck getting one of the gloves off, she can try to explain that instead... 

Merrin seems pretty scrambled!  He hopes she didn't hit her head hard enough to get a status effect.

Sure, he'll try following these, you know, actually sort of complicated instructions if you have literally never Operated a Technology in your life.

Merrin did not hit her head that hard! If she had taken any of those impacts to her head right now, she would be UNCONSCIOUS, not mildly disoriented. She just has, in Golarion terms, a perfectly normal number of hitpoints for a commoner with no class levels in anything, and she has also - somewhat remarkably given how much more than average she likes climbing trees and jumping off tall rocks, her mother has teased her - managed to go through her entire life until now without ever actually breaking a bone. It turns out! That this is really distracting! And making it hard to have original thoughts!

(She's pretty embarrassed about how impairing it is, actually, having previously observed Estha not even seeming distracted by multiple broken bones. There's probably a skill there that one can improve with practice! Merrin has just not practiced that specifically because in dath ilan a broken bone takes at least six weeks to heal so it would be really stupid to break bones on purpose for training purposes!) 

...She will eventually manage to say out loud in words that the electronics are mostly down and there might be literal mechanical damage causing the helmet and gloves to be stuck, and maybe Estha should find something to use as a lever to try to force it open?