Is there really a lot of powers or creatures that Molly doesn't know? Some Outsiders, some epic-tier olden things and so on.
Probably.
This isnt Creation that was, and Usum was out of circulation for a long time.
Its entirely plausible; the NeverNever appears to throw up new creatures every year.
The baku we see in Day One was allegedly less than ten years old, and originated from the popularity of a children's toy in Japan.
And I objected to that too, but that at least was plausible enough (if you look at it right).
As I have pointed out, so is this.
She is the daughter of an old god and psychopomp who we know has been running around for more than a thousand years, with all the family contacts thereof among the spirits, and she has been spending time onscreen improving her contacts and relations among the ghosts.
IC justification is not an issue.
Its the same justification I'm using for allowing her to buy Demon Fighter without training with Brother Devisimar; she has access to tutors and information that way.
What are you counter-pointing? We have someone with us and weren't trapped in NeverNever.
If there had been two skinwalkers there, instead of just Hank alone, and the other had gone round to attack the old dude in his carriage? Or even just an opportunistic NeverNever predator? We'd have been stranded and had to try to make our way back to the Monoc base and hope there was someone on watch at the door to let us through.
Never mind if Arianna had escaped into the NeverNever in Mexico and we had to rely on Seeker to open a Way to enter or leave. Or had to bargain with the fae if that failed.
That is a situation I do not want to put ourselves in ever again.
No it doesn't. At all. Akuma are not spirits. Animals are not spirits. All vampires are not spirits. Ghouls are not spirits. Elementals might be spirits, ok, but so far we have encountered one. Certain fae are almost certainly spirits, but not all of them are. Hell-walker technique, absent your absolutely ridiculous over-extended reading of it (and no, I won't be nicer about it, it's ridiculous) is of far narrower application than Source Code Compliance Protocol.
And this is leaving aside craft synergy. Or attack potential. Or denial of magic potential (I highly doubt that many will be able to cast while under its effects, especially if their magic has phonetic component).
We've had this argument before. You're wrong.
The spirits we see, from Bob to Dana Watson to to Doctor Miyamune to Demonreach, all speak human languages. The gods and demigods, from Meditrina Bassarid to Odin to Hades, all speak human languages. There's a plethora of once-human ghosts, who all count as spirits now, and speak/spoke (and read, and write) the various human languages from prehistory onwards.
Hell, the Unseelie Accords between all the not-human supernaturals are apparently written in a human language.
I dont recall if its old English or Latin, but its definitely human.
So respectfully, no. You're wrong.