Ye Blue Bookes of danjerus andde koruptynge knowlidge, the finalle tombe of Five Great Wizzards.
A very ornate and very old looking spell book. Chock full of spells, most of which are unreadable by any magic user. The ones that can be read, unfortunately, don’t have the affect the mage is looking for.
Like a Binding Oath Ring but it stops anyone under witness protection from revealing his or her true identity to anyone. I might make this into a submission one day.