Xenosaga(ゼノサーガ,Zenosāga) is a series of science fiction video games developed by Monolith Soft and published by Bandai Namco. Xenosaga's main story is in the form of a trilogy of PlayStation 2 video games. There have been three spin-off games and an anime adaptation. The Xenosaga series serves as a spiritual successor to the game Xenogears, which was released in February 1998 for the PlayStation by Square. The creator of both Xenogears and Xenosaga is Tetsuya Takahashi, who left Square in October 1999 along with Hirohide Sugiura. Using funds from Namco, they started MonolithSoft and the Xenosaga project.