Arcas (アルカス Arukasu ) is a creature that protects the entrance to the Fountain of Polaris and Chariot's childhood companion.
Arcas resembles a gigantic polar bear with a golden badge in the middle of the face. He is the protector of the Fountain of Polaris and fiercely attacks anyone who approaches it. However, it retains its affection for Chariot.
In greek mythology, Arcas is the son of Callisto.