Key Magic

Key Magic (鍵魔法) is a magic attribute that allows a user to create and manipulate keys.

Description
This magic attribute allows the user to create and manipulate keys at will. In order to use it to its full potential, specific spells are required, which are stored within grimoires.

These keys can be used to lock and unlock other objects. When one of the keys is used to lock or unlock something, it manifests a keyhole, either in midair or on the object being locked. When used in midair, the key manifests an ethereal door around the keyhole after the key has been inserted. Anything locked by this magic is sealed in a magical space that only the user has access to.

The user can also steal another mage's magic by using a key to lock that mage's grimoire, which causes it to turn to stone. After locking someone's magic, the user can unlock it for themselves and copy that mage's spells via the ethereal doors. The victim whose magic was locked would still be able to use basic magic, but wouldn't be able to use any of the spells in their grimoire. If the corresponding key is destroyed, the magic returns to the original mage and the grimoire is restored.

This magic is noted to be highly compatible with Imperial Sword: Elsdocia.

Trivia

 * The magic was initially going to be called "Door Magic" (扉魔法).