Xenosaga: Pied Piper is a role-playing video game co-developed by Monolith Soft, Namco Mobile, and Tom Create. The game was published by Namco in 2004 for mobile devices. A spin-off of the Xenosaga trilogy and forming part of the Xeno metaseries, the storyline follows the human life of cyborg Ziggurat 8—a key character in the Xenosaga trilogy—a century before the events of Xenosaga Episode I. Gameplay follows a similar system to the mainline Xenosaga games but adjusted for mobile devices.