E4: Anthem of the Earth
E4 kicks off a new phase in the series' thematic structure: the Couplet of Creation. It emphasizes nature and the natural world, as opposed to human culture and civilization. Taking place exclusively on the mountainous mainland of Mesomia, unlike the first three installments which were in lands to the north and south, and especially unlike E1 and E2 (which were set in the archipelago of Adamaria, where water was the predominant resource), its setting forms an ideal basis for this theme.
In the center of Mesomia is the hallowed Mt. Ostrica, whose summit is said to grace the boundary of Heaven. Many seek the power that would be found there, but the mountain is protected by the four Elemental Gods - Genbu, Byakko, Suzaku, and Seiryu - so its inhabitants, charged with guarding the summit at all costs, seemingly have little to fear. They live their lives in peace, undisturbed by the outside world and flourishing in harmony with nature.
However, down in the lowlands, rumors spread of a growing mystical society known as the Illumination. Some believe they have achieved enlightenment, but others purport that their intentions are far more sinister. And one of the Illumination, Prince Asur of Arafel, has his sights on Mt. Ostrica...