According to Papers Owl, the film incorporated the mythology of Pan through the Faun, a more twisted take on the god of shepherds. The Faun is half-goat, like his ancient Greek counterpart, but the other half is forest, not man, with tree roots instead of legs and a coating of moss around his body. Also like Pan, the Faun is shown to be lecherous, and makes advances toward the nymph Echo, who in turn rejects him. While this was common for the god Pan, the Faun reacts violently, killing Echo in a display of dominance.
The film is riddled with references to ancient Greek mythology and literature, including nods to Homer’s “Odyssey” and the myth of Cronos. The Faun serves as a central stand-in for Pan and guides the main character Ofelia on a series of trials and tests, turning the god of nature and flocks into a sort of dark trickster deity, showing how these stories can still resonate with new meanings centuries on from their origins.