I tried to interpret it myself, but end up with "thoooooooo" occupying my mind. I beg you, all the linguists in the Neath, to tell a foreign traveller what it is actually. Thank you!
[spoiler]
(1)
MAGICIAN: It’s good to see you up and about with everyone else. Wasn’t sure how adaptable your sort was. Your mantle crest seems quite -
OUTCAST: Nishe. Fffine. ("Neathy. Fine."?)
MAGICIAN: Quite, yes. But those ah, extrusions - your liminalities and, ah, that light? Surely -
OUTCASE: Thhhurvithed worttth. ("The hurt is worth"??)
(2)
CARNELIAN EXILE: You.
NACREOUS OUTCAST: Ffrhume? (??)
CARNELIAN EXILE: I want your secrets.
NACREOUS OUTCAST: Ffiefhh humth! (??)
CARNELIAN EXILE: As you will. I can wait.
(3)
CARNELIAN EXILE: You again.
NACREOUS OUTCAST: Fffrah erffuhth. ("From afar"??)
CARNELIAN EXILE: I’ve waited long enough. There’s more to you now.
NACREOUS OUTCAST: Intheth nath Frosttfhounf!("In the north Frostfound")
CARNELIAN EXILE: No. No more. The stars are hungry. I’m running out of time.
NACREOUS OUTCAST: Eatht. The Eatht.("East. The East.")
CARNELIAN EXILE: That’s all? That’s all you have for me? …d__n you. D__n every one of you. May Axile burn.
(4)
BANDAGED POISSONNIER: Just a little, now.
NACREOUS OUTCAST: Fotharoothathoth! (??)
POISSONNIER: Now, now. You’ll grow it back.
OUTCAST: Etha! Ssithakothothooth! (??)
POISSONNIER: You are not a generous soul.
(5)
NACREOUS OUTCAST: Othatooroth ithacithi? (??)
SHADY COOK: Baragerralock. (??)
(6)
CANNONEER: Hello!! I have a question for you.
OUTCAST: Fhel nafham. (??)
CANNONEER: You’re a shapeling, aren’t you?
OUTCAST: Gosph nfoo ffierreffof. (??)
CANNONEER: Do you know anything about the Red Science?
OUTCAST: Feroo. FEROO. (Error?)
CANNONEER: No, I understand, but -
OUTCAST: FERRO ieh FHESH. (Error is flesh?)
CANNONEER: Oh, suit yourself.
(And this one, may not be rubbery)
For the Shady Cook in Wisdom, there is:
"Worracoovaprisnz," he says dangerously. "Lemmesithertow!"
("Oracular prison. Let me see the ???" …toad? I’m not sure.)[/spoiler]