Villains, families, species, or groups whose real given names remain unknown if they had one to begin with (e.g. The Thing), were simply forgotten (e.g. Witch-King of Angmar), are unpronounceable by conventional language (e.g. Glgrdsklechhh) or are known only by aliases or conjectural names (e.g. Fiamma of the Right). Such villains can be Enigmatic.

Note: Villains who have official names should not be added to this category for obvious reasons or the ones who have first names but do not have last names (Mother Miranda for example) since many villains have their first names but do not have surnames.