The leader of the Research Division stationed in Demeter Market, there are many dark rumors about Maxwellia Arothron. Although he acts as one of the "Four Devas" of OLYMPUS, he is generally most feared of the four, and loses in mysteriousness only to Master of Jurakudai Villa. Maxwellia does not actively participate in battles of Duel Chart, but will be more than happy to have another "experiment" where he pits his Servant against opponent's.
Unknown at this time
A strange figure who seems to pass his time with "experiments," and utilizes chimera, among them at least one known to have withstood a Servant for a short period of time, and a female, shark-like creature called "Cadenza."