Maybe going a little off topic but perhaps it may help to expand on the fairy theme, here are a couple of ideas that are from popular myths and legends about fairies.
The whole thing with faeries is that they can be wonderfully varied, the pretty little winged butterfly tinkerbell type is but one of the more family freindly images that we may have and faeries or, "the Fey" as they are known in western european myths and legends could encompass everything and anything mysterious and unexplained from the causes of socks that go missing to that well known and malicious little dwarf from the fairy tale "Rumplestiltskin" that tricked the king into almost giving up his beautiful daughter if nobody could guess his name. There are heaps of stories out there that we I'm sure all know from when we were growing up that can be used for inspiration.
fairies could be cute little butterfly people that transform into nasty little winged monsters as the get angry, Illusions are one of their favourite tricks, stunted little people, long thin wispy people, part animal, part plant, let your imaginations run wild.
Traditionally the Fey were feared because of their charms and trickery rather than because of any physical danger they may pose (although in enough numbers anything can be dangerous), and they were always trying to steal babies or take people away from the realworld to live with them forever with only the completion of some obscure task that would save you or your lost one. here are a couple of examples of fairy situations from tales that I can remember:
Aloof and beautiful faerie queens would lure you into a clearing where a monumental feast would be occuring only to claim that you now belonged to her because you ate a mouthful of food or drank her wine, when you protest she sends you on a quest to squirt the juice of a rare fruit into the chalice of the king or some such in order to save yourself, and thus putting the king under her spell so that he loves her etc
a tricky little dwarf may meet lost travellers on the road and give them directions to a place where they will have no choice but to kill something or fetch an item for him in order to get out alive. or he will promise them treasure if they bring something (or someone) to him. then he will disapear and leave them to clean up the mess or chase him down etc.
a beautiful woman will be in great distress and promise any one who helps her a wealth in gold or her hand in marriage, and once the quest is complete she turms out to be a cackling hag.
Word plays, riddles, tricks and illusions are the main weapons of the fairies of myth. But there is a reason that people don't mess with them or disobey them as they can be extremely powerful.
hope it helps