Diadora was a high-ranking member of the Order of the One True Way who served as the head Librarian and as a personal aide to Chancellor Valfred. In truth, she was also a Wanderer, and one of the original Wanderers who had survived the world fusion which had destroyed her world, coming into possession of the Chronicle of Endless Travels.
Since then, she worked to realize the goals of the Order, but slowly began to doubt Valfred's sincerity and motivations. These doubts would be made manifest with the cold manner by which Valfred destroyed the Magedom of Janam, instantly wiping out over one million lives. Diadora would be moved by the hero who believed in the future, and decided to fight the One King again and abandoned the Order.
Armed with the Chronicle of Endless Travels, she had the ability to freely create Gateways, allowing her allies to traverse the Infinity freely with this power. Diadora was also a highly perceptive ally, acting as somewhat of an advisor, having gained great knowledge and insight over the years, especially as regards the Order.
Following the defeat of the One King, Diadora participated in reconstruction efforts across the land using her talents, before vanishing mysteriously.
Diadora's name can also be localized as "Deirdre", a less fantastical rendering. Her name is sometimes pronounced as "Deirdre" in the English language voice track for Suikoden Tierkreis, most notably by Valfred.
- Genso Suikoden Kiwami Encyclopedia, pages 748