Nithveil Adept (Druid Archetype)
The idea of a location that is normally impossible to find is a classic concept in fantasy settings, and we see that in the Golarion setting with the Town of Nithveil, a settlement tied to the First World, the realm of the fey, but which manifests randomly in the forests of the Land of the Linnorm Kings, but only on a new moon. This strange settlement is home to fey, talking animals, spirits, magical beings, and more mundane residents, and is something of a trading town, offering those who find it rare delights from the world of the fey.
While many druids have some connection to the fey, the Nithveil Adepts, or Veiled Adepts outside of Golarion, have a special connection to that ever-changing city, allowing them to serve as guides to and within the settlement, for those that dare to hire their services.
Of course, this archetype is also useful for other hidden cities and locations, both the magical and mutable, and the more mundanely hidden.
 Animal companions are not well suited for the life of these adepts, so they must choose a domain. However, if they are a worshipper of one of the fey Eldest, they can pick from among the domains granted by that being in addition to their normal choices.
With a little magic, these druids can infuse animals with the linguistic powers associated with Nithveil, allowing them to speak a single language and understand it. However, they are not any more intelligent than they were previously, which can inhibit conversation with them, but the boon to communication with others is well worth it.
Due to what they work with, the supernatural resilience druids have only applies to fey magic, but eve more so, allowing them to put a little more effort against a single such dweomer each day to better resist it.
During the new moon, or whatever period their disappearing locale appears, these druids can use their bond to find the quickest path to reach it for a visit.
Interested in a merchant or guide druid that can always find their way to a specific, hard to find locale? This archetype may be what you’re looking for. The ability to grant speech to animals can help gain additional information out of animals and defuse combat against them. Obviously, you’ll want to build with a domain in mind, particularly considering what specific Eldest the druid worships, if any.
 With their association with a settlement that spends most of its time in the First World, it only makes sense to roleplay these characters as being utterly unfazed by strangeness, particularly that which is actually just a normal part of their lives. This can make them oddballs to more contemporary companions, though.
Additionally, consider replacing a few abilities of this archetype with those of equal power that are associated with some of the strangeness of whatever your homebrew hidden realm is.
  Fleeing from a group of Giant’s Cowls (A particularly massive subspecies of executioner hoods that never mature into trappers or lurkers above), the party finds themselves in a cavern city not on any map. Asking around, they discover that they have stumbled on the legendary Caravan Cavern, an extradimensional mobile fey realm normally requiring guidance from the cavern adept druids to find.
 Armada Town, named for being composed of many repurposed boats in Herbad Bay, is protected by powerful magic, making it a perfect haven for pirates and those needing to stay hid. However, only the druids of the scaleheart skinwalker tribes along the shore know how to get their reliably, using special magic keyed to the wards of the floating town.
 The city of Moonshadow, that elusive place only found on the new moon, that is where the cure to the counts illness can be purchased. However, the fey there know of his need, and are unwilling to sell for his sake due to past crimes of his family. If the party had a negotiator druid, however…
