This mecha was built by King Gundam III, the father of the British royal family, who was passionate about mecha research. Imperial Knight III, a confident yet hardworking individual, has been familiar with this machine since childhood and can control it as if it were an extension of his own body. He also participated in the Ultimate Battle alongside Imperial Knight III.

This mecha incorporates technology not only from the Suda Doaka world but also from the fused Lion Kaji world, and is a third-generation mecha powered by the Rune Crystal. The Imperial Mecha carries the Imperial Blue Knights towards the Heliopolis Plains. Simple operations can be performed automatically.