Yuan's duel with Hotaru culminates with Hotaru exhibiting signs of crimson in his right eye. Finally beaten, Yuan uses his powers of illusion to confuse the little black cat that acts as a spy for Fubuki to keep Yuan in line with the Four Elders' wishes. He then reveals that Hotaru's sudden exhibition of crimson eyes is called "atavism". As it happens, all members of the Mibu Clan used to have the crimson eyes until they steadily disappeared; this dwindling of their genetic powers is strongly related to the greatest secret of the Mibu Clan.
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