Heffalumps and woozles are scary creatures from my favourite film of all time, Winnie-the-Pooh and the Blustery Day, which can be found as part of The Many Adventures of Winnie-the-Pooh.
After being warned by Tigger that "Heffalumps and woozles steal honey", Pooh falls asleep and has a nightmare about them. So, I imagine, do millions of children across the world.
The nightmare involves a spooky song that goes "A heffalump or woozle is very confuzle, a heffalump or woozle's very sly...". The aforementioned creatures appear in bright colours and play with yo-yo's, take part in a marching band, transform themselves into hot air balloons and other things. In particular, the bit where they "tie themselves in horrible knots" greatly disturbed me during my younger years. I wonder if those lovely people at Disney know that this seemingly innocent tale from the Hundred Acre Wood has effectively caused enormous numbers of children to have nightmares?
The film may have been aimed at children, but personally I'd give it a 12 rating.