Water Realm

The Plane of Water (水のプレーン, Mizu no Purēn) also called the Water Realm is a world that is never seen or ventured to in-game, but is mentioned throughout the course of Magical Vacation.

In Magical Vacation
Water People once lived in this realm until Enigmas came to wreak havoc. This caused many inhabitants to be separated across various realms. A group of lost Water People who ended up in the Dark Realm created Akvavit Castle, which took all the water away from Muy Mot Desert.

The first instance of the Water Realm being mentioned is when Blueberry spots a Water People in the Light Realm. Being a speaker of their Erimu language, she is able to translate its words and tell her classmates about what happened to its family in the Water Realm. As the game progresses, the party can explore Akvavit Castle in the Dark Realm to learn more about the Water People.

In Blueberry's epilogue segment, she goes to the Water Realm for the sake of her heritage. She tells stories of her adventures to the Water People there.