JSA: Our Worlds at War

President Lex Luthor calls upon the JSA during the invasion of Earth by Imperiex. They are sent into space to damage the ship Imperiex uses to provide his energy and troops. They call in everyone they have available that is not engaged in battle elsewhere and head out to the ship, described as being the size of Jupiter. Once there they find that the power source is the planet Daxam, with the people being drained of their lifeforce to power Imperiex. The JSA plans to free the Daxamites, send them home, and destroy the ship.