Lagoon

Lakeland is a prosperous country until the evil being Zerah pollutes all of Lakeland's rivers and lakes, making people very sick. He does this in hopes to release the Evil Spirit, which is hiding underneath Lagoon Castle, so Zerah lifts Lagoon Castle into the clouds to where no one can reach it. With all this, Lakeland needs a hero: Nasir, the Champion of the Light. Nasir must go through many lands, challenge many monsters, and meet many people who will help him on his quest. (Wikipedia)