Alright I got it
Since your doing a long game, I'll give you waht I did for players in very much the same situation.
THey had to be around 10 to fight it.
THe set up, is that the Nanny, in your story got taken by this creture in the woods, or w/e, someplace outside away from everything..I used a spring, but in the past used a stream.
Anway, she plucked some strange weed from the waterto use as garnish for their diner that night. However, in the kitchen, she tasted it since it smelled, or looked funny...can't serve it that way. She was then possesed.
ok, the creature was actually a tiny spore like virus that had attached itself to the plant in the stream, but theres more. THe spore, or virus as it was later classified by the cleric, was an inteligent spawn (think Venom suite from spider man) of a creature that had passed through a stream up in the mountains, and the thing then driffted down water into the area where it was found. The thing, or spawn had hive-mind while it was in the grass, but once being eaten hadd issues for a time with the nannys mind, ergo, things went on as normal. Once however that it understood where it was *it thinking that it was the whole* started to work its infulence with the king.
SO, the players found out, killed the nanny, and then through the story found out that the creature came by water, tracked it to where the source was in the river, then tracked the creatuere for several games learning that it could also move by almost any means..once found it turned out...here is where I'll let you come up with yourown ending.
But thats what I did.
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