Zarathustra

Zarathustra is a device in the Xenosaga series. It is the key to enact the Eternal Recurrence. It is also the namesake of Xenosaga Episode III - Also Sprach Zarathustra, being depicted on the logo.

Keys

 * All 12 Vessels of Anima
 * Joshua
 * Maiden of Mary's will
 * Shion's pendant
 * Shion's pendant

Story
Despite being mention multiple times throughout the trilogy, Zarathustra doesn't physically appear until Episode III.

As a boss
Zarathustra is the final boss of Xenosaga Episode III and the entire trilogy.
 * Zarathustra (boss)