Originally mentioned in Fate/Grand Order's 2020 GudaGuda event (2022 in the English server), then introduced as a welfare Ruler-class Servant for the 2022 GudaGuda event (2024 in English). Iyo is Himiko's disciple and successor to the nation of Yamatai-Koku. Designed by toi8 and voiced by Ozawa Ari.
