The year the cloud fell: In a strange, alternate-history nineteenth-century American West, President George Armstrong Custer sends his son on a mission in an experimental dirigible to chart the locations of enemy Native Americans, but the young man is forced to crash land his aircraft and is taken prisoner by the Cheyenne. Original. Genres Alternate History The Spirit of Thunder: In an alternate history of the American West, the battle between the U.S. government and the nations of the Cheyenne Alliance takes a bizarre turn when George Custer, Jr., the only son of President Custer, falls into the hands of the Cheyenne and decides to fight with them against the armies of his father. Original.