I believe the Pale Man sequence is an excellent example of the usage of mise en scene in Pans Labyrinth. The entire set is a complete disconnection from the rest of the film as it has very distinct props and set pieces that create an atmosphere of terror and worry around what will occur down there.
The walls are decorated with blood, signifying the danger and horrific events that may have taken place in that very hall previously. This immediately puts the audience on edge and makes them uneasy. This is exaggerated once we enter the main hall because at that point, we see the paintings on the wall that display the Pale man stabbing and eating a child. Because we are so invested and worried about Ofelia’s safety and we know for a fact that she is doomed to die due to the opening shot of the film, this makes the audience more wary of the surroundings, especially since the Faun warned Ofelia of the danger that lurked down there.
The Pale Man himself is masterfully crafted. By using a rubber suit rather than CGI he looks and feels human. Despite this, he sits proudly and terrifyingly at the head of the table, watching over the feast in front of him. The design choice of having his eyes in his hands causes him to be this fear inducing yet impractical and tame monster. It shows a vulnerability in him, causing Ofelia to escape unscathed from his clutches.
Furthermore, the feast is designed to target Ofelia’s main vulnerability at the time by exploiting her weakness of not having eaten for the majority of the day due to having been denied supper for being muddy and dirty. This makes the feast a symbolic way of showing how Ofelia is still a child and can disobey rules and go against the grain without questioning it.