Admiral Gyozen is a semi-retired, hardcore military man who serves as a military adviser on the GDF council. He has lost many battles against Godzilla as the captain of the Atoragon in his career. As a result, he harbors a deep-seated hatred toward all monsters. Gyozen is among the human council on Monster Island when a crystal meteor shower rained down Earth. When the council gathers, he suggests using the Atoragon to fight the monsters and shatter the crystals from underground, but his idea is dismissed by the rest of the council. Instead, he then commands Doctor Shiragami to experiment with G-Cells, which inadvertently results in the creation of Biollante. Later, he takes the Atoragon for himself and comes across one of the crystals, taking a drastic effect on his sanity, fighting whatever monster the player uses three times; once in London around halfway through the round, though fighting the Atoragon is entirely optional; then in New York, where the player's monster must fight the Atoragon until it reaches half its health; and finally in Osaka for a one-on-one boss fight, where Gyozen begins to question his reckless attacks on the monsters and influence of the crystal, but his hatred wins and he attacks the player a second time, leading to his death when the monster destroys Atoragon.