Desians (ディザイアン Dizaian?) are half-elven members of an organization in Tales of Symphonia that serve as the primary antagonists for much of the story. Viewing all other races as inferior, they set up large Human Ranches, where they cultivate humans to turn into Exspheres. Each ranch is overseen by one of the Desian Grand Cardinals.
The Desians are a group of half-elves that carry out Cruxis's will in the declining world, capturing humans and treating them as prisoners. While these humans believe the Desians are evil, Cruxis is seen as a holy organization for the highly religious and influential Church of Martel, yet few people know of their connection. As the story progresses, it is revealed that the Desians' true purpose is to enhance the Chosen's Cruxis Crystal by deliberately placing him or her in harm's way, as Cruxis Crystals only grow when the host is under stress or in danger. The Desians are instructed not to kill the Chosen, for the Chosen is needed for Cruxis's ultimate goal of beginning an era of half-elf supremacy, often referred to as the "Age of Half-Elves".