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Case (Japanese: クレイ Clay) is a character of the day who appeared in Crisis at Ferroseed Research!. He is a scientist and an assistant to Professor Malveaux, working at the Ferroseed Research Institute.
Case greeted Ash, Iris, Cilan, and Georgia when they came to visit the Institute, and he gave them a tour through the building. While doing so, however, the moss created by some of the Ferroseed broke free from one of the laboratories and began covering the building and its surroundings. Iris, her Axew, Ash's Oshawott, and Georgia's Vanilluxe became stranded on the roof, while Case and the others were able to escape.
Case then followed Iris's progress in wiping out the moss with Ice-type attacks. He later assessed how Cilan, Georgia, and Professor Malveaux were doing in saving the Ferroseed and, eventually, the Institute.