Very disappointed. GdT is my favourite director and I simply adore Pan's Labyrinth, so I was really excited when I heard about him going into this darker direction once again.
I am not scared easily, so maybe it is my fault that I found this movie not scary at all.
The antagonist, Mama, got my sympathies, for showing that she is a good being, caring for the children and playing with them, if even she had fits of jealousy later on.
Plus, since we humans are generally afraid of the Unknown, we saw her face way too often to be scared of it - frankly, her long fingers and abrupt movements were a little cliché as well, as was the ending in general.
While I did enjoy the change of Annabeth, a character I disliked in the beginning, to get closer to the children, this movie had so much potential that hasn't been acted upon.
The theme of Mama being/hiding in rot was interesting, could have been a hint that her body was rotting somewhere in the woods. Her whole backstory was interesting, nun gets pregnant, baby taken away from her, but how, a little bit more there was something I wished for. Or the father - obviously a ghost/leftover emotion as well, only had one scene.
All in all a watchable movie, but nothing close to scary with a very disappointing end.