So we're wrapping up Book 2 in a couple of sessions and I have a choice. The way my party has acted has been extremely good and honest, and anyone watching would definitely get the impression that these are people who can be trusted with secrets.
Which brings me to the Arazni encounter. I'm half thinking that the PCs will guess who she is without her saying and maybe even press her on the answer. And I'm thinking that she might be willing to tell them, based on what little she has observed of them over the first two books (and before).
Before I do that big reveal two books early, I need to think ahead to some of the complications this might bring up, as well as spoilers, changes, etc... What does the group as a whole think of this?
My only thought about revealing her too early is when they go to Vigil.
"Why did you come here?"
"Someone who seems to know more than us sent us here."
"Who were they?"
"We don't know." vs "An undead lich demigoddess known to be evil."
Also, as far as I'm aware Arazni only really becomes interested in the PCs when they get rid of the fog in Roslar's Coffer (maybe a little bit before that), so she needs to test their loyalty and willingness before she just openly reveals herself.
So one of my PCs is the daughter of a prominent Mourner of Arazni. I had her growing up in competition with Ceto and when the theft happened the PC was implicated by Ceto and sent off to Roslar's Coffer instead of facing court marshal and/or prosecution. When Arazni showed up in my game at the end of book 2, the PC knew right away who it was. However, I've instilled into the players' heads that if they went to Vigil and told them the Lich Arazni visited them, the crusaders would be dismissive at best.
It is built into the AP to clue them into her identity if your players know anything about Golarion lore. I wouldn't worry about them knowing, because no sane person would go to Vigil and start telling others that they are in league with The Harlot Queen of Geb. It was a very cool reveal at this time and allowed me to have Arazni give the players some extra lore and history of this very lengthy timeline.
Now I'm saying this as someone who has set up a second campaign where my PC's mother has already been visited by Arazni in visions. I have sent this PC to the Isle of Terror to retrieve one of her bloodstones in a ramped up City of Golden Death. We usually run this on weeks where we are missing integral PCs for the main story.
Luckily, we have a table of experienced players who are able to differentiate their PCs in each module as well as the knowledge they each hold. I don't think this will work in all cases, but I'm trying to build up the Arazni redemption angle, so more trust is better for me and my table.
I don't think it will be a huge problem for them to know. Just remember that sometimes sharing secrets can be very dangerous.
Also, as far as I'm aware Arazni only really becomes interested in the PCs when they get rid of the fog in Roslar's Coffer (maybe a little bit before that), so she needs to test their loyalty and willingness before she just openly reveals herself.
As pointed out in my original post, Arazni has been observing the PCs before even book 1 (I ran a one-off with the characters, which she took part in, disguised). At this point, she's pretty convinced that the PCs can be trusted.
As for why the PCs are going to Vigil - they're already going to Vigil (or at least to the nearest Crusader castle). One of the PCs is a cleric of Iomedae and already in the Lastwall bureaucracy. The reason to beeline for Vigil is simple - Roslar's Coffer was destroyed by agents of the Whispering Tyrant. This is well known by the PCs before they even meet Arazni.
@Twisted_Fister - cool. Yeah, that's what I was thinking as well. Unless the PCs are completely nutty, they're not going to lead with "Hey, guess who we saw yesterday...". One of the neat things I'm planning is to have a few minutes with each PC alone to "debrief" them once they get to Vigil. Certainly with the Iomedae cleric and the Aroden paladin. That'll be fun.
It sounds like you've already made up your mind, which is fine. An alternate encounter if you decide you don't want the PC's to know their benefactor is Arazni is to have it so she grabbed a rando Whispering Way cultist on their way in/out of the fog, Dominated them, and had them be the ones to meet with the PC's (after losing their cultist uniform).
On the other hand, even if the PC's meet Arazni, figure out her identity, and go around telling everyone in Vigil, it's likely their story will remain just as far-fetched and dismissalbe as written. It could create some weird NPC questions after they started convincing the various leaders of their story's validity, but I honestly don't think it would change much. Even for NPC's that would never trust Arazni, you could just justify their new motivations (once the PC's convinced them) as believing Arazni is the one behind the Whispering Way's machinations, and take the same precautions as written.
Yeah, I've pretty much made up my mind to at least have the opportunity for the reveal. The original question was more concern over whether there was some important plot point hinging on the PCs being unaware it was Arazni until Book 4. Which it appears there wasn't.
Moving on, I've decided to flavor the magic items she gives the PCs at the end of Book 2. I figure she "swiped" some serious undead-killing things from the treasury in Geb. If you think about it, Geb has to have this enormous vault of undead-bane items simply from adventurers trying to overthrow the gov't there.
So far I have a longsword Iomedae herself used early on in the Shining Crusade. It's a scalable item, so it'll reveal more powers as the character grows in level. Its for the party cleric.
If anyone has suggestions (even vague ones) about other appropriately themed items, I'm all ears. I can also post the specs for the longsword here, too.