Maleficent's appearance can frighten younger viewers.
Dark and intense images including monstrous creatures, a huge forest of thorns which comes to life, creature violence, cruel use of magic, and medieval combat.
Some areas in the magical world have a certain 'dark' feel to them, but not scary.
A winged creature is tricked into drinking a sleeping potion, and her wings are severed and taken away while she sleeps. When she wakes and realizes what has happened she screams over and over in pain and horror. While the connection is not made explicitly in the film, it has been commented that the symbolisms between this incident and rape are very clear - it is possible this imagery would be disturbing to those affected by those subjects.