Poseidon

Poseidon, also known as The Master and briefly known under the alias Don Posei, is the Olympian god of the sea, who communicates with Lady Tremaine and Facilier through the flames. They, themselves, carried out Poseidon's plans, although they were only pawns in the grand scheme of things.

Background
Lady Tremaine came to serve Poseidon, whose machinations are apparently responsible for Tremaine ensuring that her daughter Anita becomes Queen of the Red Kingdom. Facilier also serves Poseidon, having done so since living in Terra Mater.

Volume 1
After a fireplace is lit in the dining room, Tremaine makes sure she is alone before communicating with Poseidon, who reveals that the girl who Prince Roger danced with at the royal ball - and by extension, the only threat to their plans - is Ella. Later, after Tremaine's death, Facilier contacts Poseidon, who demands that whoever marries the future Queen Rose must be "one of us". He implores Facilier to be granted full access of the Red Palace, so that they can find "her".

Volume 2
Poseidon, residing in an underground cavern beneath the ocean, mulls over how his pawns have failed him. Deciding to reunite with his beloved bride - who is trapped in the Onyx Vault - by himself, Poseidon orders his son Pan to summon his other son Pegasus.

Volume 3
Poseidon goes with Pegasus to Paris, France to request that Boreas gets his daughter to obtain a powerful relic that can overpower even Zeus.

Family

 * Pan (son)
 * Pegasus (son)

Trivia

 * He is based on the sea-god Poseidon from "Greek Mythology" and the Friends on the Other Side from the Disney film, The Princess and the Frog.
 * Poseidon's bride is most likely the gorgon Medusa.