Katana is a ha'tak spaceship which serves as the home and base of operations of the Goa'uld Raiden, as well as the flagship of his ha'tak fleet that constantly roam from world to world in his domain.

By using the Katana as a mobile base of operations, Raiden is made harder to find by his enemies. Katana also carries the Stargate which was formerly based on the planet Kyoto, and can be used for outbound trips when the ship is in orbit of a planet with a Stargate, but can only be accessed from other Stargates when Katana orbits Kyoto. (RPG: "Fantastic Frontiers: Stargate Season One")