"Really, all you need to do is - if I'm suddenly struck by lightning, pull me back out of range, please."

She has a rope and everything all ready.  And when that's set up, she'll approach the Mysterious Magical Bullshit.

"This fucking house."

The room as filled with Mysterious Magic Bullshit as she left it last time. 

As she enters the room, it starts to gather around her, and the air gets even thicker.

Does it become any more legible as it does so?

It still doesn't do analytical legibility - she can't see any structure to it beyond concentration of power, but if she focuses on it, she can get a feeling of what it does - it's similar to looking at an Archon's power, though much more lowkey - it doesn't have a structure, but it has a vibe - protection, stopping, warding. 

She can notice it's harder to move now, except in the direction she came from.

"Interesting.  This power isn't structured as a Sigil would be, though it has a...taste, like one; it's more reminiscent of a relic, or an Archon.  Of Forces, perhaps, or reminiscent of some of the seemingly-inexplicable things the Archon of Time was reputed to be able to accomplish that one would have thought had nothing to do with time and the progression thereof...And even discounting Icarix, who was unusually absurd even by Archons' standards, we have the example of Nerat's Sigil-based instantaneous transportation, the Illusory False Pit, and Bleden Mark's ability to see and reach through shadows...Regardless, though, it is a ward, and it presses back against me as I push forward in equal measure, seeming...oh, hmm, Stasis.  That's only been proven in an accent, but...hmm..."

She thinks she has a trick for this, come to think of it.

(She has more than one in mind, actually.)

Perhaps if she Unravels the Mind of the ward with the one hand, and deploys a Mirror Image with the other so that the resultant confusion settles on pushing those mirror images and not herself...

Well.  First, she declaims the following: "I have had this conversation with the gate; I have passed through it, needing naught besides my right.  I am the duly-acclaimed Librarian of Hush House, and naught that is of Hush House shall bar the Librarian about their duty, nor shall that whicn is not of Hush House be allowed to remain to so impede Librarians - so reveal your purpose to me or stand aside.  This is your first and only warning, before I resort to measures."

"I think it might be one of van Lauren’s forbiddings, though it’s unusual that it is here, this part of the House was open to visitors."

The magic does not react to her proclamation. 

"Well.  Having words with it didn't work."

"...Let's see if doing some twisty corkscrew thinky shit does.  It's helped with Sigils before."

She'll just back out of the magic for right now, and untie the rope she's probably not going to need for this.

...Actually she's going to see if she can lasso something within the forbiddance's area of effect, since the rope is already there anyway...

But first, she needs to inhabit the mindset of Van Lauren.  Why would this forbiddance be here?

For that particular question, she has advantage over Timothy in that she can see the concentration of magic - it seems stronger the further up the stair she looks, and the parts in the room seem flow-y. Perhaps, it wasn’t originally here at all…

"...why the fuck would it...spring a leak?"

"Huh. Well, many things can spring a leak in seven unattended years. Didn’t expect that, but I guess it makes some sort of sense."

"More sense than anything else has made.  It's mystery cults all the way down, I swear..."

...Anyway.  With the theory that this is, somehow, spontaneously-arising loose aspected mana...

"...I wonder if I could use this for, effectively, a crafting material.  Metaphysically speaking."

"Should I be ready to pull you out?"

"I don't believe myself to be in particular danger, but that's no excuse to slack on safety precautions.  But what I should first do, is actually design a proper ritual for this.  I'm thinking that I want to convert all this leaky forbiddance into book wards. Because this is a library, and our books sha'n't be left to suffer preventable harm if we can help it whatsoever, I think."

"Indeed. I have no idea what previous librarians did about it, though I think there must've been something."

"Presumably magic, or not having this particular problem."

"Hmm..."

What she has is Force over Influential Domain, and what she needs is Preservation over Material Form...So how can she get there from here?

...Via the Forge-bind.  But that hasn't exactly been worked out as a Sigil proper, and she doesn't have the right drugs to try looking, so what can she do that would still be like?  Fire, Force again, Stone, perhaps...And that's not really even considering Influential Domain to Material Form, no matter that the Forge-bind does have relevant elements...

(To say nothing of how this is absolute auroch dung, magic-theoretically - but she's an Archon, dammit.  She's going to bullshit the shit out of this shit.)