Oracle Keys

The Oracle Keys are fractions of the Oracle's power. They take the form of a card that can be split in two. The Invectids hope to gain them for Mantid who wants to use their power to rule Arachna, which is why the Oracle uses much of her strength to protect them. The Spirit Oracle Key passes its power onto Hunter and Shadow, giving them new armor and weapons as well as new abilities.

To activate these keys, the holder must shout "Oracle's Light!". Two in combination can create more powerful armor and weapons. The wielder must have a sincere desire to protect without arrogance, otherwise the keys will not work. The Oracle Key from Nuuma was called by Corona (using her power) to let Hunter use it without him actually holding it.

Mantid had used two of the Oracle's keys to power himself, plunging the Inner World into darkness and preventing Hunter from using his own keys.

Currently four of the locations of the four Oracle Keys are known in the English version:
 * 1) Found in the Oracle's shrine in Arachna, the first key is taken by Hunter and Shadow, who retain possession of it throughout the series.
 * 2) The second key is brought to Arachna by a page from Nuuma. Hunter and Shadow have it in their possession for most of the series, though it was briefly taken by Aqune and Portia.
 * 3) The third key is initially kept in a sanctuary in Nuuma and allows the castle to float in the sky via the Oracle's power. It is taken by Aqune for the Invectids, but eventually ends up in the possession of Hunter and Shadow during the final battle against Mantid.
 * 4) The fourth key held by Mantid, powering both Castle Mantid and sustaining Mantid himself, throughout the series until he steals the Oracle's power and abandons it. It ends up in the possession of Hunter and Shadow during the final battle against Mantid.

These keys hold the power of the Spirit Oracle. When Hunter uses them, they upgrade his and Shadow's attack, defense, and speed:
 * 1) Arachna Blade (never said in the anime)
 * 2) Blue Bolt
 * 3) Blue Wave
 * 4) Electra Twist