White Wolf (please don't hurt me) had a supplement called Midnight Circus which could provide some interesting starting off points as far as populating your "fun fair" or, as we call it in Maine, "Smokey's Greater Deathtraps."
As far as what the main creature could be... I had been thinking of what might happen if a Corpse Candle possessed a nasty little wizard. Perhaps the CC had been a woman burned as a witch or a child lost by accident. So maybe there's this house, or only a piece of ground, the CC inhabits. Along comes this weasly wizard who runs more to the illusionist idea and BAM he gets possessed.
Now maybe this happened a while ago, and the wizard has slowly gone mad. He's built up this imaginary troupe around himself for company, an illusionary carnival. They wander from town to town, looking for all the world like the real thing, and while they're there some people disappear (the CC trying to find its killer) and then they move on. No one can ever find them because they aren't always in existence.
So you could have all kinds of fun with this imaginary carnival - populate it with the worst monsters and horrors - and all the PC's really have to fear is the possessed mage himself. In that respect, you'd have to tone him/her down a bit - their madness making them less of a direct threat (and more of an indirect one).
I just have this scene in my head of a bunch of PC's lost in the mirrormaze while this twisted, half-burnt little thing chases them screaming "Are you the ones that did it!? ARE YOU THE ONES!" and images of them catching on fire are reflected in the mirrors...
As far as what the main creature could be... I had been thinking of what might happen if a Corpse Candle possessed a nasty little wizard. Perhaps the CC had been a woman burned as a witch or a child lost by accident. So maybe there's this house, or only a piece of ground, the CC inhabits. Along comes this weasly wizard who runs more to the illusionist idea and BAM he gets possessed.
Now maybe this happened a while ago, and the wizard has slowly gone mad. He's built up this imaginary troupe around himself for company, an illusionary carnival. They wander from town to town, looking for all the world like the real thing, and while they're there some people disappear (the CC trying to find its killer) and then they move on. No one can ever find them because they aren't always in existence.
So you could have all kinds of fun with this imaginary carnival - populate it with the worst monsters and horrors - and all the PC's really have to fear is the possessed mage himself. In that respect, you'd have to tone him/her down a bit - their madness making them less of a direct threat (and more of an indirect one).
I just have this scene in my head of a bunch of PC's lost in the mirrormaze while this twisted, half-burnt little thing chases them screaming "Are you the ones that did it!? ARE YOU THE ONES!" and images of them catching on fire are reflected in the mirrors...