Blown Away! The Battleship Rengoku, Stop Its Sails!

Sanosuke, Saito, and Kenshin go to Osaka to find Shishio and his men onboard a ship. They find Shishio, and Shishio launches the Purgatory, a steel-plated battleship he paid a fortune to get. Shishio plans to use the Purgatory to launch an assault on Tokyo.