Xenogears (ゼノギアス Zenogiasu?) is a science-fiction role-playing video game developed and published by Squaresoft (now Square Enix) for Sony's PlayStation. Xenogears follows protagonist Fei Fong Wong and several others as they journey to uncover the truth behind mysterious, cabalistic entities operating in their world. The relationship between humanity and machines is central to the game's plot, as indicated by the presence of giant robots dubbed "gears," which almost each playable character can control. Xenogears initially takes place on Ignas, the largest continent of the Xenogears world, and the site of a centuries-long war between the nations of Aveh and Kislev. A church-like organization known as the Ethos has excavated gears, ostensibly for the preservation of the world's culture. Although Kislev originally had the upper hand in the war, a mysterious army known as Gebler appeared and began to provide assistance to Aveh. With Gebler's help, the Aveh military not only recovered its losses, but began making its way into Kislev's territory. As the story unfolds, the setting broadens to encompass the entire world and the two floating countries, Shevat and Solaris. Solaris, ruled by Emperor Cain and the Gazel Ministry, commands the Gebler army and the Ethos and secretly uses both to dominate the land-dwellers. Shevat has been the only country to evade the control of Solaris. Much of Xenogears plot and backstory is detailed in the Japanese-only book Xenogears Perfect Works. This book, produced by the now defunct DigiCube, details the history of the Xenogears universe from the discovery of the Zohar to the start of the game. According to the Perfect Works schematic (as well as the game's end credits), Xenogears is the fifth episode in a series of six.