I Transmigrated to Another World with the Empire's Entire Technological Might Behind Me

Colonel Schneider and Dr. Victor used a time-space device to transmigrate to the year before their defeat. They knew the empire could no longer be saved because of the stubbornness and incompetence of its leaders. This time, they decided to abandon their cooperation with the empire's core leadership and use the advanced technology at their disposal to open a gate to another world, where they would restore the empire's glory!