Nameless OneSource Arcane Anthology pg. 15
You completely eschew your former identity, making you impossible to locate or even name.
Benefit: A character with this feat eschews all of her former identities, going as far as to render her former name completely inaccessible by mortal means. You perform an 8-hour ritual that requires the expenditure of 200 gp for rare oils, incense, and creation of a special mask. After this ritual, you forever lose all names and identities previously associated with you (including any identities that you gain from class abilities). You adopt a brief descriptive title in place of a new name. Your title must not reference the names of any people or places. (For example, you could adopt the title “Blue Fox” or “Night Stalker,” but not the title “Chelish Avenger” or “Spirit of the Mwangi.”)
At the ritual’s conclusion, you must don the mask created for the ritual, the appearance of which is evocative of your title. While you’re wearing this mask, any attempts to scry or otherwise locate any of your eschewed identities or connect you to those identities do not work, revealing nothing but darkness, as if you were an invalid target or did not exist. Successful Knowledge checks to identify you reveal your new title rather than any old identity, but can reveal your strengths and weaknesses normally.
As long as you wear the ritual mask and do not reveal your connection to any past identities, any attempt to scry on you independent of your eschewed identities requires a successful caster level check with a DC of 10 + your hit dice. In addition, you are immune to effects that require the use of your name, such as the named bulletUC spell. While benefiting from this feat, you cannot wear any magic items in the head slot, as the mask used by this effect effectively occupies this slot (though this benefit is not magical for the purpose of dispel magic and other effects). In addition, you cannot attempt to impersonate a specific individual by any means, magical or nonmagical. If you ever reveal or confirm your connection to your eschewed identities, you immediately lose the benefit of this feat and gain 1d4 permanent negative levels as your discarded identities return. You cannot regain the benefit of this feat or remove these negative levels until you atone (as per atonement, as if restoring a class feature).