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Talk:Story
"(A system comprised of three planets, like Algol from the original Phantasy Star games, if you discount the 'hidden' fourth planet)"
Ryukros actually doesn't count toward the three planet configuration. While there are more than three planets in Algol, only the main three (Motavia, Dezolis, and Palma) and the sun constitute the seal which binds the Profound Darkness away. Ryukros is more of a warning star for the guardians - a sort watchtower for the few remaining members of the spiritual race which makes up the Great Light.
The three planets of Gurhal (Parum, Moatoob, and Neudaiz) as well as the seal on the ruins of PSO (Mutt, Dittz, Poumn) are all symbolic of the same type of seal.