Unfortunately, the game starts in an hour, so no time for research reading.
The main point is that Sceadrau is a light fey, vaguely wolf-like, who is 'saving' non-fey by healing their bodies and reanimating them as hybrids. I want to avoid a heavy Island of Dr. Moreau feel, so there are only four hybrids living with her, most of them former members of the PCs' village who were lured away over the past few years. Sceadrau rescued the remains of some from the feasts of the dark fey, and brought them back. One should be a half-bear/half-ogre, since the town will later be threatened by ogres and I want to show that some are nearby. Another will be a githyanki, because there's a portal to the astral plane in the woods, creating a manifest zone in the woods where the fey court resides. That's where I want the final encounter to take place.
Subjective-directional gravity, quickened spells, and timelessness. Oh yeah baby.
Okay, what I think will happen:
The group has a farewell send-off by their town. They get a compass, and one of the town's hunters sends a dog and a pack mule with the party. The town's smith gives her apprentice a small metal dagger she fashioned out of metal from a meteor. One of the town mages gives the group a wooden wand with three charges of 'wood shape,' which can affect a 10-ft. cube. The town mayor -- who always seems to know more than she should -- gives them beer.
They head into the woods. The journey is about thirty miles, through uneven terrain, so it'll probably take two days, if they succeed a few Survival checks. I want a non-combat encounter in the normal woods, like maybe a bear crossing their path (they'll see that it's using the same trail as them), just to get the flavor. And I might make an 'encounter' out of hunting if they don't want to waste their supplies.
Then they reach the edge of the fey woods. The boundary is, of course, not clear. The trees simply start getting a bit denser, the sounds more vivid, and eventually they realize they can barely see the sky overhead or the path twenty feet ahead.
They travel a bit more, see horse tracks, follow them to water, which leads to safe place to rest. This is near a cave where the wood medusa (I need a name) lives. She comes out while the group is sleeping, ambushes one of the party, and drags him off to her lair. She'll actually target the most attentive person, since she wants a reaction on the face of the one she turns to wood. She's serpentine, but slithers among the trees, stalking them with poisoned hallucinogenic arrows. When things go badly, she'll burst into leaves and drift away laughing.
After that, one PC should be injured. When they set out again, a few hours of wandering later, they find Itana, but soon the mist surrounds them, we have a spooky luring by the lantern-bearer (who wants the PCs to do his dirty work for him, so he lures them to Sceadrau) and we end with the attack by a warthog-taur and a mockingbird that sits on the shoulder of a faceless human with a whip and a dagger.