Satyr

Satyrs, less commonly known by the Roman term Fauns, are creatures with the upper body of a man and the lower body of a goat complete with hairy goat legs and hooves, as well as goat horns, and pointed ears that look like those of a goat's. When in public, they tend to be clumsy, for they have to wear fake feet so that the sound of their hoof beats won't draw unwanted attention.

Description
Satyrs are monsters that work for Camp Half-Blood and go out into the world to search for demigods. While searching, they wear disguise, such as fake feet or hats that hide their horns. It is possible that the Mist cannot hide all of a satyr's features however, as a flight attendant of Tristan McLean's saw Gleeson Hedge's hoof, but passed it off as just seeing things as well as Percy giving Grover his shoes in The Lightning Thief so that the life guards wouldn't see Grover's hooves. Many went to search for Pan, the ancient god of the Wild, until he faded. Most of those satyrs were lured to Polyphemus' Island because of the overpowering scent of the Golden Fleece during their search for Pan and then eaten. Others, such as Ferdinand were attracted to other monsters for reasons unexplained.

The most commonly known satyr is Grover Underwood, the best friend and guardian of Percy Jackson. Grover was sent to search for demigods and found Percy, so he became a friend of Percy. He had to make sure that Percy stayed out of trouble, which was hard with Percy being the son of Poseidon (his scent was powerful and drew monsters from far away). Satyrs also worship the god Dionysus. They also seem to appreciate the goddess Artemis as she is "so into nature", as stated by Grover.

Roles
Many satyrs go to Camp Half-Blood to become a Searcher. A role of which they will usually conduct a search of Pan, the god of the Wild. Long ago, Pan disappeared, as the modern civilization was tearing apart the wild. Afterwards, in The Battle of the Labyrinth, Percy, Grover, Tyson, Annabeth, Nico, and Rachel find Pan in a nature paradise where Pan fades and soon he gives his role as Lord of the Wild to Grover.

Fauns
Fauns are the Roman form of satyrs. At Camp Jupiter, fauns are opposite of satyrs. All they do is lounge around and beg for money and are used for amusement purposes.

Abilities

 * Can detect half-bloods and monsters (but not underground) by scent.
 * Can control plants and insects by playing music on their reed pipes.
 * Can talk to animals.
 * Have animal-level hearing and smell
 * Can eat recyclable material (tin, aluminum, plastic, etc) and even wood and grass
 * Run at superhuman speeds, along with climbing, as a result of goat legs
 * Can sense nature magic (such as the Golden Fleece, Pan, and gifts of Pan)
 * Can sense emotions of demigods and of Mortals.
 * Woodland magic.
 * When they die, they are reincarnated as plants or trees, such as laurels, (if they are lucky) and flowers (the average satyr).

Notable Satyrs

 * Grover Underwood
 * Leneus (deceased)
 * Gleeson Hedge
 * Silenus
 * Maron
 * Ferdinand (deceased) (Grover's uncle, as revealed in The Lightning Thief he was turned to stone by medusa)
 * Lysas (deceased, satyr sent by Pan to spread the word of the Lord of the Wild's death)

Notable Fauns

 * Don

Trivia

 * Oddly, in the myths, Satyrs are described as creatures with wild desires, making the choice of them to collect young demigods, particularly girls, slightly questionable in nature.
 * There Roman term Faun, probably derived from the Faunus, which happens to be the Roman counterpart of Pan.
 * At Camp Half-Blood, satyrs sit at the Dionysus table for meals, along with his demigod children and Dionysus himself.
 * In some Roman myths, Fauns were thought to have a large poetic imagination.
 * In Camp Jupiter, fauns are treated as annoying beggars while in Camp Half-Blood, they are more important as they are Keepers and Searchers.