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Room decorations
From The re-PSUPedia
Room decorations come in a wide variety of sizes and styles to help add a more personal touch to your room. Many can be purchased at Clyez City's Variety Shop and Casino Voloyal's prize counter, however you will come across even more unique decorations through item synthesis. (That includes synthesis failures, too!)
Remember that decorations which are exclusive to Ambition of the Illuminus can be placed only in rooms that have been remodeled with an Illuminus remodeling ticket.