Lost Winds of the Fallen Kingdom

The realm of Hoshimi was once a strong kingdom divided into four territories: Fire Lands, Earth City, Water Village, and Wind Tribe. The four territories balanced each other out, and the kingdom was prosperous; that is, til the day came when the people of the Wind Tribe vanished without a trace. The kingdom was thrown out of balance, and soon fell. Hoshimi was erased from history, and everything was lost. The once grand castle became ruins, and the people of the three remaining territories hid themselves... 500 years later, a lone adventurer by the name of Rikki wanders into the forgotten lands of Hoshimi and stumbles upon the ruins of its ancient castle. While exploring the castle grounds, Rikki finds a boy named Nao and discovers this place is more than meets the eye. Even after being disconnected from the rest of the world for centuries, the people of the lost kingdom still live and have yet to abandon their homeland! And with the appearance of Nao, the 500 year old question resurfaces; just what did happen to the Wind Tribe?

(The cover says something different because that used to be the name. I'll change it later.)