S2·E25 Raid! Legendary Armada

Q4's Aichi and Kamui face off against Leon and Sharlene of Dreadnought in the finals of the Hong Kong Stage. Remembering Leon's fight with Daigo, Aichi and Kamui do their best to minimize the damage taken from Dreadnought's multi-attacking Aqua Force units. Although Aichi deals damage to Leon, he is unaffected by his attacks. Then, Aichi asks Leon what he means whenever he refers to the "wind". It is then revealed that Leon's "wind" is actually the power of Psyqualia. In a Psyqualia-induced vision, Leon tells Aichi a tale from long ago about a conflict between the many clans on the planet Cray. This war was eventually resolved by the appearance of the dominating Aqua Force armada. In the human world, the Souryu family had control over the Aqua Force which was used to hold power over the seven seas. However, for unknown reasons, the Aqua Force clan disappeared, and so did the Souryu family's power.