Ar Nosurge

The people of the destroyed planet Ra Ciela struggle to survive on the Soreil, a massive spaceship constructed by their distant ancestors. Their existence is threatened by mysterious beings called Sharl, which can use the Song Magic that was lost to humans long ago. In response, Soreil's people have split into two warring factions; the Genomirai Church seeks coexistence between the species, while the city of Felion believe they can only achieve peace by destroying the Sharl. (mobygames)