27 characters in the Lydian Unicode block.
U+10920LYDIAN LETTER AU+10921LYDIAN LETTER BU+10922LYDIAN LETTER GU+10923LYDIAN LETTER DU+10924LYDIAN LETTER EU+10925LYDIAN LETTER VU+10926LYDIAN LETTER IU+10927LYDIAN LETTER YU+10928LYDIAN LETTER KU+10929LYDIAN LETTER LU+1092ALYDIAN LETTER MU+1092BLYDIAN LETTER NU+1092CLYDIAN LETTER OU+1092DLYDIAN LETTER RU+1092ELYDIAN LETTER SSU+1092FLYDIAN LETTER TU+10930LYDIAN LETTER UU+10931LYDIAN LETTER FU+10932LYDIAN LETTER QU+10933LYDIAN LETTER SU+10934LYDIAN LETTER TTU+10935LYDIAN LETTER ANU+10936LYDIAN LETTER ENU+10937LYDIAN LETTER LYU+10938LYDIAN LETTER NNU+10939LYDIAN LETTER CU+1093FLYDIAN TRIANGULAR MARK