Demonic Summoning Stone

Description
Double-click to summon a [sic] Oni ally of your level that lasts for 30 minutes or until slain in combat. Summoning stones can only be activated once every 60 minutes per character, and only one ally from a summoning stone can be present in an instance at a time. This item can only be used in explorable areas.

Acquisition

 * The Deep
 * Kanaxai's Chest