There are certain character names that you can no longer create because of the character name filter. Upon the development of Tibia, this filter became more and more restrictive. This doesn't make those names illegal though - they can just no longer be created and therefore can be considered rare.
Examples
Loqhakk - Applying to TibiaQA team as ModeratorJuly 26, 2024
Nareull - Applying to TibiaQA team as ModeratorJuly 14, 2024
Looking for new TibiaQA staff membersJuly 12, 2024