This potent relic radiates Legendary summoning and protection magic. It is made from a skull of some mythic humanoid being, the bone pure white and polished, each rough edge or ridge gilded with purest gold. Lines of tiny seed pearls, topaz and onyx form a swirling pattern across the Skull's smooth dome, winding down and around the empty eye sockets that seem to gleam with their own inner light. Magical examination will reveal the Skull as a potent artifact of good.
The Skull is designed as a trap for Demonic beings. Discovering the rituals involved in actually using the artifact requires three Superb tests of ritual lore (the GM should determine what sources are required to make these tests as suits their campaign). Preparing for each of the rituals involving the Skull requires a Great test of ritual magic, with the material requirements for each representing a one-time Superb cost to obtain the proper accouterments. The three rituals are outlined below:
Ritual of Snaring - This ritual allows the Skull's owner to trap a demonic being within it's magical protections. To carry out this ritual requires the demonic being be present on the mundane plane, either of its own accord or after being summoned. Once present the appropriate ritual must be complete, which requires the aforementioned research and ritual tools be available. Completing the ritual requires five Good tests of ritual magic. While attempting the ritual, the Skull's owner may only focus on the task at hand. They are subject to attack by the target demon unless other preparations are made -- protective devices, defenders, etc. Once the ritual is completed the target demon must make a Legendary resistance test against summoning magic or be compelled to enter the Skull. Once snared they are held in stasis until released or banished. The Skull may hold up to three lesser or one greater demon at a time.
Ritual of Banishing - This ritual allows the Skull's owner to banish a trapped demon from the mundane plane. This ritual requires five Good tests of ritual magic in a row. Each failed test gives all demons contained within the skull a chance to escape its confines. To escape the demons must make a Legendary resistance check against summoning magic, gaining a one rank bonus to this test with each failed ritual magic test. Demons successfully banished are forced to return to their plane of origin and cannot return on their own accord for 666 days. Demons that are freed during the ritual are free to do what demons do best, cause chaos and destroy their foes, beginning with the Skull's owner.
Ritual of Compulsion - Using this ritual the Skull's owner may call forth a trapped demon and force it to serve their will for ten rounds, after which the demon will return to the Skull's confines. This ritual requires a single Good test of ritual magic, though each demon contained within the Skull is granted a chance to break free with each invocation (Legendary resistance check vs. summoning magic). This ritual may be used no more than once per cycle of the moon.