Ah, right. Well, once the quarryers have gotten through it, you see that the downward-sloping passage continues.
Scott
Gregorius will request one of Fray's glowing rocks from him, and then proceed down the passage with Alcimus (and probably Fray?)
Fray will also proceed down the corridor.
(Ooc: away with family for a few days, happy to cast anything akin to what has been cast before)
Traveling down the winding passageway, you can see that, up ahead, the stream empties into an underground pond, or maybe even a lake--you're not yet close enough to be sure how big it is. Before you get there, though, Gregorius notices a regio boundary in the middle of the passage. Looking inside, he sees a similar passageway, leading toward what appears to be (rapidly waning) daylight.
Scott
Gregorius points.
"Careful - there's a regio boundary there."
Is the positioning of the regio boundary such that people are likely to stumble through it by accident? And how easy would it be to go round it and proceed in the normal world for now?
Editted to add: And what time is it in the real world?
It's the type of regio you have to see to enter, so no, no one could stumble into it by accident.
It's about sundown.
Scott
Gregorius hesitates.
"I'm not enthusiastic about leaving the regio entrance to our backs, but the light appears to be going in there, and I'd rather explore it when it's not dark. Also, it looks as though the regio reflects at least to an extent the real world, so exploring down the passage may well give us an idea of the geography inside the regio. The good news is it's almost certainly magical, or my sight wouldn't be able to spot the boundary."
He'll proceed onwards towards the water.
[OOC: I'm assuming he's not getting any particular bad feelings?]
It depends on how you intepret that rule...but remember that Gregorius has a high Perception and a reasonably high Second Sight, and you're in an aura of 5, so the bonus to his roll is over 10.
Nope.
Scott
[OOC: +12 for regiones, I think, assuming a level 5 aura still The ease factor for seeing into a foreign aura from a magic aura is going to be 5 + 2 x ( Magic Aura + foreign aura), so I suppose the ease factor would only be 17 for a level 1 foreign aura, which is doable (I'm not sure whether you can have lower level foreign aura, although the text on how regiones are formed implies you might be able to). Or he could have just rolled really well if it was a stress die, of course.]
Anyway, on down the mundane passage to the water!
I've seen a forum thread where someone used that formula, but is it anywhere in the books?
Gregorius finds that the pool at the end of the stream is not all that large--maybe a dozen paces across--though it does fill up most of the cave. There don't appear to be other exits.
Scott
[Rules for seeing regio boundaries are on Page 189.]
Hmmm. So there are no obvious exits, but water would normally flow into here. It's possible it just completely fills the cave and then stagnates, but that wouldn't explain why it wasn't completely full when the blockage was removed. Alternatively, there may be another exit from the cave he hasn't spotted yet...
Gregorius will spend a bit of time searching the cave for any additional ways out. To help in this he'll cast the following spells:
Non-fatiguing aura check.
Eyes of the Cat at Personal Range, MuCo(An) 4. Casting total (Mu 0 + Co(An) 1 + Sta 1 + Aura 5? + die 7) = 7, works. (invisiblecastle.com/roller/view/4483920/)
Clear Sight of the Naiad, to see clearly through the water, in case there's an exit there (rolling up duration in the unlikely event he can): (In 6 + Aq 0 + Sta 1 + G 1 + Aura 5? +die 9)/2 = 11 - so he can extend it to concentration duration assuming the aura is what I think it is.
Oh, I didn't realize that bit was in the main rules. Seems on the uworkable side, but OK.
Whoops, my mistake--yes, the magi can see that the pool is still filling, having been dry for a while. They can also see a hole which is almost certainly the outlet through which the stream continues. There don't appear to be any proper exits, though.
Scott
[I don't think we undid the blockage to allow water to start flowing yet?]
How big is the hole? (Bigger/smaller than person size?)
Oh, that's right. Well, the pool goes up to the bottom of the hole. The hole is big enough for the stream, but crawling down it would be a tight fit.
EDIT: Actually...it's been over 15 years, so the pool would have dried up by now.
Scott
[OOC: I assume the aura was still 5?]
Gregorius spends a bit of time peering down the hole, then comments:
"I suppose the sensible way to locate where it comes out would be to let the water flow again, get a small piece of Herbam material, cast a spell to locate it on it, then drop it down the stream. Assuming it didn't become really obvious the moment we started the stream flowing, at any rate. It's that or shrinking, anyway."
He'll wait to see if Fray has any observations or bright ideas (or just wants to know why Gregorius actually cares).
Failing that, he's going to post a guard at the waterfall end of the tunnel, then come back for the regio in the morning. He'll suggest to Fray that he brings a shield grog with him, although will understand if he'd rather just rely on his shapeshifting.
I think you'd be both shocked and disappointed if it weren't.
As for the rest, I'll wait for ironbound's reply.
Scott
"The guard at post is an excellent suggestion. I do not want unwelcome visitors around my lab."
[OOC question: I assume that I can spont cast the same "fish gills" spell on a form I've transformed into? i.e. change my size to an animal, then to be very small, and then get fish gills too, in case I need them?
Another question: is the tunnel something that a crow could fly down, or perhaps a small child could climb? ]
If so, then Fray will suggest he morphs into a smaller shape, and travels down the tunnel.
"I could use an animal form to travel into the hole and see where it goes. If it empties anywhere I might be able to find it, but I'll hesitant about what risks there might be too".
Since Fray isn't a Bjornaer, I think the canonical answer is that yes, it will work--he's still Corpus.
Where it exits this chamber, a child might crawl down it, but flying would be difficult. Who knows what it looks like further down?
At a small size, this could take hours; also, there might be something in there that might want to eat little Fray. You sure you want to do this?
Scott
Not sure at all. Curious vs Patient personality 
"Hmm, as tracking a leaf or other material is safer, perhaps I'll wait to see what outcome that has "
"Let's go with the leaf idea, then, but wait until after we've explored the regio tomorrow morning before releasing the stream."
He'll retire and post the guard (who should have some way of creating an alarm that can be heard up above - a bell or a horn or something).