It appears that an Earth Kingdom was planned, but eventually not implemented. Each kingdom is ruled by a monarch who is capable of powerful magic. Sia's kingdom, Myriade, is separated from the elemental realms by the Snowy Mountain and located in the southern part of the continent.
An Earth Kingdom was originally conceived but not implemented. Each kingdom is ruled by a monarch endowed with powerful magic. Sia's kingdom, Myriade, is separated from the elemental realms by the Snowy Mountain and located in the southern part of the continent.