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Shusoran is a Layan kingdom situated on a large island in the Aquatica dome of the Alisa III. The kingdom enjoys close relations with Cille, another nearby Layan kingdom. Lyle, a prince of Shusoran, is the nephew of Cille's king.
Relations between Shusoran and another neighboring kingdom, Agoe, are not as friendly. Agoe is an Orakian land and the two kingdoms are often at war. Shusoran is the stronger of the two, with Agoe unable to defeat them. Due to this conflict, the castle of Shusoran is heavily fortified and fountains in the town became legendary for the appearance of Biomonsters in the fountains. Many citizens of Shusoran have a deep hatred and fear of Orakians. Lyle is an exception, perhaps thanks to his friendship with Rhys.
If Rhys marries Maia, they and Lyle guide Cille and Shusoran into a time of peace. The war with Agoe is ended. Anti-Orakian and Anti-Layan sentiments among the dome's citizens are overcome as Rhys and Lyle ascend to their respective thrones. The peace ends when a mysterious army of cyborgs attacks the Layan lands, eventually driving the inhabitants from the dome. Survivors later settled on Satellite, where many of their families lived until the destruction of that moon.
In the event that Rhys does not marry Maia, the details of Shusoran's later history are unclear. The land is still overrun by the cyborg army. The fate of survivors, if there are any, is not known.